2021 International Conference on Laser, Optics and Optoelectronic Technology - LOPET 2021 28th -30th May 2021 Orient Hotel Xi'an, China ZOOM ...
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2021 International Conference on Laser, Optics
and Optoelectronic Technology
（LOPET 2021）
28th -30th May 2021
Orient Hotel Xi'an, China
ZOOM Conference ID：975 129 3611
Organizer
AEIC Academic Exchange Information Center
Conference Chairs Prof. Changsi Peng, Soochow University, China Prof. Nianqiang Li, Soochow University, China Prof. Xiao Yuan, Soochow University, China Organizing Committees Prof. Shengjun Zhou, Wuhan University, China Dr. Hani Kbash, Aston University, UK Prof. Abbas Zarifkar, Shiraz University, Iran Dr. Farshad MIRAMIRKHANI, Isik University, Turkey Dr. Patrice SALZENSTEIN, Centre National de la Recherche Scientifique, France Dr. Lee Siang Chuah, Universiti Sains Malaysia, Malaysia Dr. Graciana Puentes, Universidad de Buenos Aires, Argentina Prof. Salman Noach, Jerusalem College of Technology, Israel Prof. Chandra Shakher, Center for Sensors, Instrumentation and Cyber Physical System Engineering, India Dr. Andrey Pryamikov, Prokhorov General Physics Institute of the Russian Academy of Sciences, Russia Assoc. Prof. Paulo Pereira Monteiro, University of Aveiro, Portugal International Technical Program Committees Prof. Jingsong Li, Laser Spectroscopy and Sensing Laboratory, Anhui University, China Prof. Xiaotian Li, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, China Prof. Koichi Shimizu, Graduate School of Information, Production and Systems, Waseda University, Japan Prof. Manuel Filipe Costa, Universidade do Minho, Portugal Prof. Jannick Rolland, Institute of Optics, University of Rochester, USA Prof. Mohammed M. Shabat, Islamic University of Gaza, Gaza Strip, Palestinian Authority Dr. Chong Leong, Gan, Micron Memory Taiwan Co. Ltd. Dr. Rajib Biswas, Indian Institute of Technology Tirupati, India
TABLE OF CONTENTS Conference Schedule ................................................................................................................................................. 1 Conference Agenda .................................................................................................................................................... 2 Session I：Keynote Speeches ...............................................................................................................................................2 Session II: Keynote Speeches & Presentations...................................................................................................................3 Keynote Speeches....................................................................................................................................................... 6 Keynote Speech 1: Laser patterning induced quantum structure arrays by molecular beam epitaxy.........................6 Keynote Speech 2: Vortex-mode-based Communications in Optical Fiber...................................................................7 Keynote Speech 3: Boosting efficiency of GaN-based light-emitting diodes................................................................8 Keynote Speech 4: Polarity control of III-nitride and approaches in the development of high efficiency AlGaN- based deep UV-LEDs .............................................................................................................................................................9 Keynote Speech 5: Noninvasive measurement of physiological parameters inside living animal using NIR light scattering ............................................................................................................................................................................... 10 Keynote Speech 6: Quantum cascade laser spectroscopy for gas sensing application .............................................. 11 Keynote Speech 7: Optically pumped spin-VCSELs ..................................................................................................... 12 Keynote Speech 8: Angular Filtering in High Power Laser System with Transmitting Volume Bragg Gratings. 13 Keynote Speech 9: Design and characterization of optoelectronic oscillators and optical resonators .................... 14 Oral Presentations ................................................................................................................................................... 16 1-1 Reconstructing temperature field images by MWIR and LWIR based on uncooled IRFPA............................. 16 1-2 A Novel On-line Textile Color Measurement System............................................................................................. 16 1-3 Plasmonic hollow fibers for SERS detection of liquids .......................................................................................... 17 1-4 A real-time matching system for large-small field of view images based on Zynq ............................................ 17 1-5 Study on preparation mechanism and luminescence property of CaAlSiN3：Eu phosphor ............................. 17 1-6 Numerical study of the time-delay signature concealment and bandwidth enhancement in semiconductor ring laser ........................................................................................................................................................................................ 18 1-7 Research on MEMS Biaxial Electromagnetic Micromirror Based on Radial Magnetic Field Distribution .... 18 1-8 Large-area metasurface fabrication via anodized aluminum oxide template method ......................................... 18 Poster Presentation .................................................................................................................................................. 19 2-1 120º Optical Hybrid Based on 3×3 Multimode Interference Coupler ................................................................... 19 2-2 Facile Synthesis of ZnO/PdSe2 Core-Shell Heterojunction for Efficient Photodetector Application.............. 19 2-3 Vapor-Phase Growth of CsPbBr3 Microcrystals for Highly Efficient Pure Green Light Emission ................. 20 2-4 Design of secondary lens focusing mechanism for multispectral camera ............................................................ 20 2-5 Study on MoS2-SiO2 Nanofilms Prepared by Sol-Gel Method............................................................................. 21
2-6 A Synchronous Control System Designed for Underwater Single-photon Range-gated Imaging Based on FPGA ..................................................................................................................................................................................... 21 2-7 LED Plant Lighting System Design Based on Improved Pigeon-Inspired Optimization Algorithm ............... 22 2-8 Effect of Laser Rust Removalon Surface Roughness of 3Cr2Mo Die Steel ........................................................ 22 2-9 Research on spectral combining technology of multi-single emitter diode laser based on composite grating 22 2-10 Study on Heat dissipation of VCSEL Array with High Heat Flux ...................................................................... 23 2-11 Analysis and design of a square-law detector based on multiplier for high linearity radiometer ................... 23 2-12 Study on the Wigner distribution function of semiconductor laser ..................................................................... 23 2-13 All-fiber Q-switching laser using thulium-doped fiber saturable absorber ........................................................ 24 Instructions for Presentations................................................................................................................................. 25 Notice for Participants............................................................................................................................................. 26
Conference Schedule
Time: 28th -30th May 2021
Location: Mudan Room（牡丹厅）, Orient Hotel Xi'an
Date Time Activity Venue
13:00-17:00 Registration Lobby (大厅)
28 May
th
Changle Room (长乐厅)
18:00-20:00 Dinner
2nd Floor
08:30-10:35 Keynote Speeches
Mudan Room (牡丹厅)
10:35-10:45 Group Photo and Tea Break
29th May 3rd Floor
Morning
10:45-12:05 Keynote Speeches
Changle Room (长乐厅)
12:00-14:00 Lunch
2nd Floor
14:00-15:20 Keynote Speeches
15:20-15:30 Tea Break
Mudan Room (牡丹厅)
29th May 3rd Floor
15:30-16:50 Keynote Speeches
Afternoon
16:50-18:30 Oral & Poster presentations
Changle Room (长乐厅)
19:00-20:00 Dinner
2nd Floor
1Conference Agenda
Session I：Keynote Speeches
Session Chair: Prof. Jinsong Li
Mudan Room (牡丹厅), Orient Hotel Xi'an 08:30-12:05, Saturday Morning, 29th May 2021
Time Title Speaker Affiliation
08:30-08:35 Opening Address Prof. Changsi Peng Soochow University,
China
08:35-09:15 Laser patterning induced quantum structure Prof. Changsi Peng Soochow University,
arrays by molecular beam epitaxy China
09:15-09:55 Vortex-mode-based Communications in Prof. Yang Yue Nankai University, China
Optical Fiber
09:55-10:35 Boosting efficiency of GaN-based light- Prof. Shengjun Zhou Wuhan University, China
emitting diodes
10:35-10:45 Group Photo and Tea Break
10:45-11:25 Polarity control of III-nitride and Prof. Wei Guo Ningbo Institute of
approaches in the development of high Materials Technology and
efficiency AlGaN-based deep UV-LEDs Engineering, Chinese
Academy of Sciences,
China
11:25-12:05 Noninvasive measurement of physiological Prof. Koichi Waseda University, Japan
parameters inside living animal using NIR Shimizu
light scattering
2Session II: Keynote Speeches & Presentations
Session Chair: Prof. Yang Yue
Mudan Room (牡丹厅), Orient Hotel Xi'an 14:00-18:30, Saturday Afternoon, 29th May 2021
Time Title Speaker Affiliation
14:00-14:40 Quantum cascade laser spectroscopy for gas Prof. Jinsong Li Anhui University, China
sensing application
14:40-15:20 Optically pumped spin-VCSELs Prof. Nianqiang Li Soochow University, China
15:20-15:30 Tea Break
15:30-16:10 Angular Filtering in High Power Laser Prof. Xiao Yuan Soochow University, China
System with Transmitting Volume Bragg
Gratings
16:10-16:50 Design and characterization of Dr. Patrice Université de Bourgogne
optoelectronic oscillators and optical Salzenstein Franche-Comté (UBFC),
resonators France
Oral Reconstructing temperature field images by Jiahong Li Beijing Institute of
1-1 MWIR and LWIR based on uncooled Technology, China
IRFPA
Oral A Novel On-line Textile Color Xiao Wu Beijing Institute of
1-2 Measurement System Technology, China
Oral Plasmonic hollow fibers for SERS detection Yunyun Mu Beijing University of
1-3 of liquids Technology, China
3Oral A real-time matching system for large-small Zhiyu Fu Beijing Institute of
1-4 field of view images based on Zynq Technology, China
Oral Study on preparation mechanism and Lei Chen Xuyu Optoelectronics Co.,Ltd,
1-5 luminescence property of CaAlSiN3：Eu Shenzhen;
phosphor Research Insititute of
Tsinghua University in
Shenzhen, China
Oral Numerical study of the time-delay signature Penghua Mu Yantai University, China
1-6 concealment and bandwidth enhancement in
semiconductor ring laser
Oral Research on MEMS Biaxial Shihao Xu Shaanxi University of Science
1-7 Electromagnetic Micromirror Based on and Technology, China
Radial Magnetic Field Distribution
Oral Large-area metasurface fabrication via Bintao Du Southeast University, China
1-8 anodized aluminum oxide template method
Poster 120º Optical Hybrid Based on 3×3 Xue Zheng Huazhong University of
2-1 Multimode Interference Coupler Science and Technology,
China
Poster Facile Synthesis of ZnO/PdSe2 Core-Shell Zhengtian Shi National University of
2-2 Heterojunction for Efficient Photodetector Defense Technology, China
Application
4Poster Vapor-Phase Growth of CsPbBr3 Shangui Lan Huazhong University of
2-3 Microcrystals for Highly Efficient Pure Science and Technology,
Green Light Emission China
Poster Design of secondary lens focusing Rui Wang University of Chinese
2-4 mechanism for multispectral camera Academy of Sciences, China
Poster Study on MoS2-SiO2 Nanofilms Prepared Jianan Xie Xi'an University of
2-5 by Sol-Gel Method Technology, China
Poster A Synchronous Control System Designed Peng Zhou CAS Key laboratory of Space
2-6 for Underwater Single-photon Range-gated Precision Measurement
Imaging Based on FPGA Technology, Chinese
Academic of Sciences, China
Poster LED Plant Lighting System Design Based Zhenxing Ming Hubei University of
2-7 on Improved Pigeon-Inspired Optimization Technology, China
Algorithm
Poster Effect of Laser Rust Removalon Surface Shiguang Liu Qingdao University of
2-8 Roughness of 3Cr2Mo Die Steel Technology, China
Poster Research on spectral combining technology Tianze Zhao Beijing University of
2-9 of multi-single emitter diode laser based on Technology, China
composite grating
Poster Study on Heat dissipation of VCSEL Array Xu Liu Beijing University of
2-10 with High Heat Flux Technology, China
5Poster Analysis and design of a square-law detector Shuai Dong Key Laboratory of Microwave
2-11 based on multiplier for high linearity Remote Sensing, Chinese
radiometer Academy of Sciences, China
Poster Study on the Wigner distribution function of Jing Li Beijing University of
2-12 semiconductor laser Technology, China
Poster All-fiber Q-switching laser using thulium- Chaoyu Xu China University of
2-13 doped fiber saturable absorber Geosciences (Wuhan), China
6Keynote Speeches
Keynote Speech 1: Laser patterning induced quantum structure arrays by
molecular beam epitaxy
Prof. Changsi Peng, Soochow University, China
Changsi Peng, Dr, Professor, received his PhD in 1998. During 1998 - 2001, he was working as
an associate professor in Institute of Physics, Beijing, China and an STA fellow in ETL, Tsukuba,
Japan; In 2001, he joined as a stuff member in Tampere University of Technology, Tampere, Finland;
By the end of 2009, he was invited as a distinguished professor by Soochow University, Suzhou,
China. He has published 1 book (Springer) and 4 book chapters, 19 granted patents and 180 papers
in peer-reviewed journals and international conferences with citations about 2000 times.
Abstract:
We have demonstrated a new approaching to grow defect-free site-controlled InAs/GaAs quantum dot
arrays (QDAs) by molecular beam epitaxy (MBE). A unique novel MBE system was combined with
in-situ laser interference patterning (isLIP). Indium atoms are selectively desorbed away from the
GaAs substrate at sites of high light intensity generated by isLIP during MBE growth, encouraging
selective nucleation and resulting in the highly controllable periodic formation of two dimensional
defect-free QDAs.
Nanostructured materials are at the forefront of 21st century device innovation. The path of
technological progress now takes us to dimensions of a few nanometers, at which structured materials
interact at the dimensions of molecules and have electronic properties governed by quantum
interactions. There is enormous potential to transform our approaches to computing, sensing,
communications, diagnosis and even perhaps the treatment of disease. Yet we do not possess all the
tools to develop the devices required at this challenging dimension. We need to explore innovative
production methods which could overcome the limitations of conventional routes and become key
enabling technologies for the second quantum revolution. Our research on site-controlled QDAs is one
such novel approach, which seeks to develop a transformational process for quantum-structure-arrays
(QSAs). The method combines the top-down isLIP with the capabilities of bottom-up structuring by
self-assembly, to provide a cost-effective state of the art capability for next generation ordered QSAs.
The resulting arrays will have unprecedented site and dimensional control and will be free of process
defects.
6Keynote Speech 2: Vortex-mode-based Communications in Optical Fiber
Prof. Yang Yue, Nankai University, China
Prof. Yang Yue received the B.S. and M.S. degrees in electrical engineering and optics from
Nankai University, China, in 2004 and 2007, respectively. He received the Ph.D. degree in electrical
engineering from the University of Southern California, USA, in 2012. He is a Professor with the
Institute of Modern Optics, Nankai University, Tianjin, China. Dr. Yue’s current research interests
include intelligent photonics, optical communications and networking, optical interconnect,
detection, imaging and display technology, integrated photonics, free-space and fiber Optics. He has
published over 200 peer-reviewed journal papers and conference proceedings, four edited
books, >50 issued or pending patents, >100 invited presentations. He is an Associate Editor for
IEEE Access, and an Editor Board Member for three other scientific journals. He also served as
Guest Editor for eight journal special issues, Committee Member and Session Chair for >50
international conferences, Reviewer for >60 prestigious journals.
Abstract:
As a newly explored dimension, spatial division multiplexing (SDM) has been demonstrating great
potential to tremendously increase the data capacity in optical communication systems. Recently,
optical communications SDM channels carried by vortex modes have gained much attention. In this
talk, we will first introduce the basics of optical vortex and its various applications. Next, we will
discuss the potential of using vortex modes for SDM in a ring fiber, including mode-division
multiplexing (MDM) and wavelength-division multiplexing (WDM) of vortex modes with 1.6-Tb/s
data capacity through 1.1-km of ring fiber. Furthermore, newly designed air-core ring fiber for
supporting 1322 vortex modes and multi-ring air-core fiber supporting a total of 2280 vortex modes at
71550 nm will be introduced. These ring fiber designs have great potential to increase the spectral
efficiency and the overall capacity in fiber-based communications systems.
Keynote Speech 3: Boosting efficiency of GaN-based light-emitting diodes
Prof. Shengjun Zhou, Wuhan University, China
Prof. Shengjun Zhou received the Ph.D. degree from Shanghai Jiao Tong University,
Shanghai, China, in 2011. He is a Professor at Wuhan University. His current research interests lie in
the areas of GaN-based LEDs, photonics and semiconductors, nanoimprint lithography and direct
laser writing with applications in electronic and photonic devices. He is well known as an industrial
technologist. Prior to joining Wuhan University, he was a CTO at Quantum Wafer Inc. from 2011 to
2014, focusing on the development of high brightness GaN-based LEDs. He was a research fellow at
University of Michigan, Ann Arbor, from 2014 to 2015. He received many academic awards including
National Youth Talent Support Program, distinguished Young Scholar of Hubei province, Chutian
Scholar of Hubei province, and Luojia Young Scholar of Wuhan University. He has published more
than 70 papers and holds over 20 patents. He is Co-chair of the Organizing Committee for IEEE
ICEPT 2016 conference. He served as committee member for many conferences.
Abstract:
GaN-based light-emitting diodes (LEDs) have attracted considerable interest for their applications in
solid state lighting, automotive front lighting, and full-color displays because of their high luminous
efficiency, low energy consumption, long operation lifetime, and broad spectral range spanning from
ultraviolet to red wavelengths. The light extraction efficiency of GaN-based blue/green/ultraviolet
LEDs is relatively low due to total internal reflection (TIR) of the generated light at the nitride-air
interface resulting from their very different refractive indices. This talk will outline the emerging
challenges in light extracting micro/nano-structure designs for boosting efficiency of GaN-based
blue/green/ultraviolet LEDs. Exploratory research in developing efficient light extracting micro/nano-
structures, such as surface texturing, patterned sapphire with silica array, reflective electrode, wavy
sidewalls, nano-prisms, embedded air void microstructure, distributed Bragg reflector (DBR), polymer
grating, laser stealth dicing, and nanoscale Ni/Au wire gird, will be discussed. Moreover, the recent
development in flip-chip LED, vertical LEDs, and Mini/Micro-LEDs will also be introduced.
8Keynote Speech 4: Polarity control of III-nitride and approaches in the
development of high efficiency AlGaN-based deep UV-LEDs
Prof. Wei Guo, Chinese Academy of Sciences, China
Prof. Wei Guo received PhD degree from North Carolina State University. He then joined
Advanced Materials Inc. as a research engineer, focusing on process development of cutting-edge
Sym3 TM ICP etching equipment. Prof. Guo joined Ningbo Institute of Materials Technology and
Engineering, Chinese Academy of Sciences in 2016, His current research interests include AlGaN
thin film growth, development of UV-LEDs/ UV-Photodetectors, and GaN-based HEMT devices.
Current achievements are: 1) Initiate the research on “lateral-polarity-structure” UV-LED with
significantly enhanced light emission, and development of the hypothesis of 3D band diagram which
can be widely used in III-nitride community; 2) Utilize MOCVD growth optimization and offcut
angle modulation, obtain a record-high IQE value of 92% and EQE value > 3.7% in DUV
wavelength region; 3) Development of self-powered UV photodetectors and self-isolated GaN
HEMT devices with polarity control scheme. Prof. Guo has published more than 50 journal articles
with citations higher than 1000.
Abstract:
AlGaN based deep ultraviolet light-emitting-diodes (DUV-LED) have attracted numerous attentions
in the application of UV disinfection, and NLOS communication. However, the development of
AlGaN-based UV-LED is still in its infancy compared to InGaN-based blue and green LEDs owning
to varies scientific and technical challenges including poor crystalline quality, strong quantum-
confined-stark-effect, and UV absorption by p-GaN and metal contact.
In this talk, we first discuss our recent progress on DUV-LEDs grown miscut sapphire substrates. High
internal quantum efficiency as high as 92% was demonstrated, thanks to Al and Ga phase separations
and consequently carrier localization effect in the active region. The correlation between micro-scale
current distribution and surface morphology was provided, suggesting that current prefer to flow
through the step edges of the epitaxial layers under low injection current. Furthermore, ECCI images
and cross-sectional TEM indicate that Ga-rich stripes are not associated with underlying threading
dislocations, therefore poses no damages to the stability of UV-LEDs.
Secondly, we will discuss the influence of polarity control and existence of “inversion domain
boundaries” in the electroluminescence property of DUV-LEDs. A “lateral-polarity-structure” (LPS)
is proposed, where III- and N-polar domains were grown simultaneously side-by-side on a single
wafer. After inserting an AlGaN/AlN superlattice and V/III ratio modification during growth, the
9surface morphology of N-polar domain is greatly improved, leading to a single peak emission at
wavelength of 275 nm in both III and N-polar domains, and 10-fold stronger peak intensity at the
inversion domain boundary. The existing of nanoscale “inversion domain” was also discovered in AlN
thin film as revealed by HR-TEM. Surprisingly, these inversion domains are fully eliminated after high
temperature thermal annealing, suggesting that thermal treatment is an ideal approach in recover the
crystalline quality of AlN and benefits the fabrication of DUV-LEDs.
Keynote Speech 5: Noninvasive measurement of physiological parameters inside
living animal using NIR light scattering
Prof. Koichi Shimizu, Waseda University, Japan
Koichi Shimizu received M.S. (1976) and Ph.D. (1979) degrees, from University of Washington
(UW), Seattle, USA. He was Research Associate in UW 1974-79. He was an Assistant-, an Associate-
Professors, and a Professor in Hokkaido University, Sapporo, Japan in 1979-2016. He is currently a
Professor Emeritus of Hokkaido University and a Professor of Waseda University, Kitakyushu, Japan.
He has been engaged in the studies of biomedical engineering including those of wave propagation
in biological media, optical measurement, biotelemetry and biological effects of electromagnetic
field. He served as an associate editor of IEEE Trans. ITB in 1999–2007. He has been a Fellow of the
Electromagnetics Academy, and an editorial board member of Scientific Reports, Nature.
Abstract: Near-infrared (NIR, 700-1200 nm wavelength) has relatively high transmission through an
animal body. However, the light is strongly scattered in animal tissue that makes quantitative analysis
difficult. We have developed some techniques to control and to suppress the scattering effect. Using
these techniques, we can visualize the internal structure of animal bodies with the safe and convenient
NIR light. This method has been applied to visualization of internal physiological functions and 3D
trans-body imaging. Instead of suppressing the scattering, we can also utilize it for biomedical
applications. As a result, we can now measure the blood turbidity from body surface without sticking
a needle for blood sampling.
10Keynote Speech 6: Quantum cascade laser spectroscopy for gas sensing application
Prof. Jinsong Li, Anhui University, China
Prof. Jingsong Li has completed his PhD Hefei Institute of Physical Science (HIPS), Chinese
Academy of Sciences (CAS), China and postdoctoral studies from Reims University (France), Max
Planck Institute for Chemistry (Germany), and visiting scholar from Swiss Federal Laboratories for
Materials Science and Technology (Switzerland). In 2013, he joined Department of Physics and
Materials Science, Anhui University (AHU), as a Professor fellowship. Currently, he is the director
of Laser Spectroscopy and Sensing Lab, Anhui University. His research interests focusing on
development and implementation of mid-infrared quantum cascade lasers and sensitive spectroscopy
techniques for atmospheric chemistry, soil ecosystems and environmental applications, and advanced
digital signal processing algorithms. He is a member of Chinese Society for Optical Engineering
(CSOE), SPIE, IEEE, OSA and EGU. He has been an invited reviewer of more than ten international
SCI journals for many years. He has published more than 60 papers in reputed journals and has been
serving as an invited reviewer of more than ten international SCI journals, tens of invited conference
presentations, and now in charge of several projects including two National Natural Science
Foundations of China, and one National Program on Key Research and Development Project.
Abstract: Tunable diode laser absorption spectroscopy (TDLAS) is an excellent method for trace gas
detection, since it presents advantages of high sensitivity, good selectivity, fast response and high
temporal resolution. With the rapid development of laser fabrication technology, quantum cascade
lasers (QCLs) have emerged as attractive laser sources for mid-infrared (MIR) spectroscopic
applications. In this paper, state-of-the-art quantum cascade laser based TDLAS gas sensor is
demonstrated as a promising new tool for high resolution molecular spectra and for noninvasive, real-
time identification and quantification of trace gases in environmental atmosphere monitoring and
isotope analysis, human breath gases diagnosis, gas exchange process between soil and atmosphere,
and Volatile Organic Compounds (VOCs) analysis and remote sensing, etc.
11Keynote Speech 7: Optically pumped spin-VCSELs
Prof. Nianqiang Li, Soochow University, China
Nianqiang Li received the B.S. degree in communication engineering and the Ph.D. degree in
optoelectronics from Southwest Jiaotong University, China, in 2008 and 2016, respectively. His
thesis work concerned nonlinear dynamics of semiconductor lasers and its applications to secure
communications and random number generation. From 2013 to 2014, he was a Visiting Scholar
with the Georgia Institute of Technology (Georgia Tech), USA. From 2016 to 2018, he was with
the School of Computer Science and Electronic Engineering, University of Essex, as a Postdoctoral
Researcher focusing on a collaborative EPSRC funded project in U.K. From May, 2018 to
December 2018, he was with the School of Electrical Engineering and Computer Science,
University of Ottawa, Canada, working on microwave photonics. He began to work in Soochow
University as a full professor since January, 2019. He has authored or co-authored more than 70
peer reviewed journal papers. He is currently working at School of Optoelectronic Science and
Engineering, Soochow University, Suzhou, China. His current research mainly focuses on the area
of the laser dynamics, chaos-based communication and random number generation, and microwave
photonics. He is an Associate Editor of the IEEE ACCESS.
Abstract: Spin-polarized vertical-cavity surface-emitting lasers (spin-VCSELs) are known to support
high-frequency continuous birefringence-induced oscillations whose frequency is not determined by
the relaxation oscillation (RO) mechanism usually recognized in conventional laser diodes. However,
this depends on the pumping condition as well as some key parameters, since electric pumping or
hybrid pumping only results in damped high-frequency birefringence-induced oscillations. Here we
focus on the optically pumped spin-VCSELs which have not been fully understood compared to those
under hybrid pumping. We consider both periodic and continuous-wave (CW) regimes for exploiting
high-frequency operation. The two regimes are restricted by the Hopf bifurcation boundaries. In the
periodic regime, the regions of period-one oscillations are identified via bifurcation diagrams and peak
amplitude curves/maps, where the dependence on some key parameters is systematically studied. In
the CW regime, we explore the high-frequency polarization modulation. In particular, double peak
response curves are found when spin-VCSELs are pumped with a certain polarization degree and the
RO frequency related peak in the frequency response curve is extremely sensitive to the variation of
the polarization degree, which leads to rich modulation dynamics in spin-VCSELs. Additionally, the
effects of the spin relaxation rate on the polarization modulation bandwidth are illustrated by using
two-parameter bandwidth maps. These findings help us better understand the underlying high-
frequency dynamics of the optically pumped spin-VCSELs.
12Keynote Speech 8: Angular Filtering in High Power Laser System with
Transmitting Volume Bragg Gratings
Prof. Xiao Yuan, Soochow University, China
Xiao YUAN, Ph.D, Professor. From 2002-2009, he was working as deputy director in State Lab of
Laser Technology, Huazhong University of Science and Technology, and he joined Soochow
University in 2009. His current research interest mainly focuses on the area of the high power laser
technology, micro-structured optical devices, optical sensing, etc.
Abstract: The uniform near field distribution and focusing property of laser beams, closely connected
with the high spatial frequencies and wavefront distortion of beams, are very important for high energy
and power laser applications, such as laser processing and laser fusion, etc. The deformable mirror and
traditional spatial filtering are used to compensate for the wavefront distortion and filter out the
medium and high frequencies, respectively. However, these methods are complex and expensive.
Moreover, the medium and high distortions in laser beams are difficult to correct with the deformable
mirror and traditional spatial filtering. The transmitting volume Bragg gratings (TBGs) recorded in
photothermosrefractive glass (PTR) has the high diffraction efficiency, excellent Bragg selectivity and
high damage threshold. Angular filtering based on TBGs can be used to clean the amplitude
modulation of laser beams, which may be a simple method to compensate for wavefront distortion.
Angular filtering with volume Bragg gratings in photothermorefractive glass was described. The
spatial distribution of the laser beams is evaluated with near-field modulation and near-field contrast
ratio. The results showed that the cutoff frequency was improved, the near-field distribution of output
beam through the angular filtering is better than that of the incident laser beam, and the low-frequency
loss of near-field angular filtering is less than 1.7%. Besides, the wavefront distortion corrected with
TBGs is demonstrated with a 1035nm laser beam, and Strehl ratio of filtered beam is increased from
0.91 to 0.98, which has potential applications in high energy and power laser applications.
13Keynote Speech 9: Design and characterization of optoelectronic oscillators and
optical resonators
Dr. Patrice Salzenstein, Université de Bourgogne Franche-Comté (UBFC), France
Dr. Patrice Salzenstein, Post-Graduate Engineering school degree (Lille, Eudil'93) and Ph.
D in Electronics, University of Sciences and Technologies of Lille (USTL'96), worked between 1996
and 2001 near Paris, France, at Thomson CSF LCR (now THALES-TRT), Alcatel Alsthom
Recherche (now NOKIA), LCIE private research laboratories. He managed a calibration laboratory
(phase noise and short-term stability of frequency) between 2002 and the beginning of 2012. He has
been working since 2001 for CNRS, a government-funded research organization under
administrative authority of France's Ministry of research, at FEMTO-ST institute in Besancon, in
Electronic Engineering domain. In 2010, one of his articles was featured in Electronics Letters for
his participation with Czech and Swiss colleagues to the best frequency stability ever measured on a
quartz crystal oscillator: 2.5×10-14 at 5 MHz. Between 2010 and 2017, his fields of interest in
research were for optoelectronic resonators and oscillators for microwaves photonics applications.
He is now with the Micro nano Science & Systems department of CNRS UMR 6174 FEMTO-ST
laboratory. His current interest is in Brillouin Scattering Stimulation. He authored or co-authored
more than 90 articles in peer review journals and international conferences.
Abstract: Optoelectronic oscillators represent a field of investigation that needs to be better defined.
It is first necessary to build such oscillators from different elements. Then we must in particular being
able to evaluate the performance in terms of phase noise of such oscillators. These oscillators can
involve optical delay lines or optical resonators whose performance must be evaluated and which must
be characterized. Here we present principles, then concrete examples with results
14Oral Presentations
1-1 Reconstructing temperature field images by MWIR and LWIR based on uncooled IRFPA
Author: Jiahong Li
Affiliation: Beijing Institute of Technology, China
Abstract: With the development of high-performance IRFPA, temperature field image measurement has been
applied to the fields of industry and agriculture, national defence, health and epidemic prevention. In order to
obtain a clearer and more accurate image of temperature field, we developed a coaxial beam splitting medium
wave/long wave dual-band infrared temperature field image reconstruction experimental system using uncooled
wide-band IRFPA. Then, a low frequency noise correction method in gradient domain is used to reduce the
temperature measurement error caused by the non-uniformity of detectors. The temperature measurement error
of central field of view is less than 3.5% and that of quadrangular field of view is less than 4.5% in the
temperature range of 20~80C by calibrating the temperature of the system using blackbody. Experimental
results show that the method is effective. Finally, the equivalent temperature field image to the typical outfield
image is given.
1-2 A Novel On-line Textile Color Measurement System
Author: Xiao Wu
Affiliation: Beijing Institute of Technology, China
Abstract: In the fields of coloring, printing and dyeing, color is one of the most important indicators for product
quality evaluating. It is helpful to monitor and control color quality in time if on-line measurement is used in
production process. Textiles vibrate irregularly when moving along the production line and most materials have
texture, which make it difficult to measure color accurately. To solve this problem, both illumination uniformity
and sampling aperture size should be studied. In this paper we designed a novel on-line textile color
measurement system. In the system, the lighting path was designed with a four-edge light pipe, which achieved
the illumination uniformity of 90%. The suitable size of sampling aperture was found by comparing the
influences caused by measuring distance changing and surface texture when using sampling apertures of
different sizes. Finally, the system has been tested for repeatability of color measurement and the result was
0.02, which showed that the performance of the system has already met the requirement for on-line textile color
measurement. Compared with similar foreign products of the same level, this system has simpler structure and
lower price.
161-3 Plasmonic hollow fibers for SERS detection of liquids
Author: Yunyun Mu
Affiliation: Beijing University of Technology
Abstract: Plasmonic nanostructures consisting of silver-gold-alloyed nanoparticles (Ag-Au-ANPs) are
fabricated on the inner wall of a hollow fiber. The Ag-Au-ANPs are synthesized chemically and dissolved in
acetone to prepare a colloidal solution, which is flowed through the hollow fiber multiple times so that it is
coated onto the inner wall of the hollow fiber. Annealing at 400◦C enabled melting/aggregation of the metallic
nanoparticles and consequent formation of closely arranged plasmonic nanostructures fixed solidly on the inner
wall. Surface enhanced Raman scattering (SERS) mechanisms are thus established, which are utilized for
detecting low-concentration molecules in the liquids flowing through the hollow fiber. The SERS measurements
show an enhancement factor >104 in the direct detection of R6G/ethanol solution. Confinement of the excitation
laser energy inside the hollow space makes an additional contribution to the enhancement mechanism.
1-4 A real-time matching system for large-small field of view images based on Zynq
Author: Zhiyu Fu
Affiliation: Beijing Institute of Technology
Abstract: Aiming at the requirement of real-time matching between the large field of view image of the night
vision goggles on helmet and the small field of view image of the infrared rifle sight in the individual
observation and sighting system, this paper uses the Zynq heterogeneous embedded platform and adopts the
software and hardware co-design method to build a system that can match the two images in real time.
Experiments show that when the large field of view image is 640×480 pixels, the small field of view image is
200×200 pixels, and the frame rate of the two cameras is 25 frames per second, this system’s matching frame
rate reaches 23 frames per second, which meets the needs of real-time matching. The system has a certain
degree of robustness to rotation and zooming, and its matching accuracy is high.
1-5 Study on preparation mechanism and luminescence property of CaAlSiN3：Eu phosphor
Author: Lei Chen
Affiliation: Xuyu Optoelectronics Co.,Ltd, Shenzhen; Research Insititute of Tsinghua University in Shenzhen
Abstract: Eu doped CaAlSiN3 phosphor was successfully prepared by high-temperature solid phase method
using Ca2Si5N8: Eu as major raw materials. The phase transition and luminescence properties were studied in
detail. It is found that the phase changes from Ca2Si5N8 to CaSiN2 when the temperature reaches 800 ℃. Then
CaAlSiN3: Eu phosphor was synthesized by the solid phase reaction: (Ca,Eu) SiN2+AlN (Ca,Eu) AlSiN3 when
the reaches 1500 ℃. The morphology and luminescence properties of CaAlSiN3：Eu with different Eu
concentration was also studied.
171-6 Numerical study of the time-delay signature concealment and bandwidth enhancement in
semiconductor ring laser
Author: Penghua Mu
Affiliation: Yantai University
Abstract: In this contribution, the effects of injection parameters, i.e. the frequency detuning and injection
strength, on time-delay signature (TDS) concealment and bandwidth enhancement of the three cascade-coupled
semiconductor ring lasers (SRLs) are numerically investigated. The results show that, under the proper
conditions, both the TDS elimination and bandwidth enhancement can be reached in the third SRL of cascade-
coupled system.
1-7 Research on MEMS Biaxial Electromagnetic Micromirror Based on Radial Magnetic Field
Distribution
Author: Shihao Xu
Affiliation: Shaanxi University of Science and Technology
Abstract: An electromagnetically actuated dual-axis MEMS scanning micromirror for lidar applications is
introduced, besides a novel radial magnetic field actuation system is designed. The dual-axis scanning
micromirror with large aperture which the plate size of 2.6 mm in diameter was realized utilizing patterned
single-turn electroplated copper coils, which combined with a concentric permanent magnet assembly forming
radial magnetic field. Based on the basic of this working principle, the displacement response outputs of
different torsion beam structures were compared by theoretical analysis and finite element simulation. The
serpentine elastic beam was chosen as the external torsion axis of the micromirror device because of its large
displacement output. The coupling magnetic field of the permanent magnet assembly was analyzed and
simulated to achieve the maximum magnetic field intensity at the coils. Horizontal resonance frequency of the
presented micromirror was 3376.2 Hz and vertical resonance frequency was 419.46 Hz, in addition, maximum
deflection angle of approximately ±25.2°in horizontal direction and about ±17.4°in vertical direction were
achieved at resonance. The design of the micromirror meets the requirements of MEMS lidar for large mirror
size and wide scanning field of view.
1-8 Large-area metasurface fabrication via anodized aluminum oxide template method
Author: Bintao Du
Affiliation: Southeast University
Abstract: Advances in the design and fabrication of metasurfaces result in the development of several ultrathin
optical metadevices, such as holography, lenses, wave plates and broadband pass filters. However, the efficiency
of metasurfaces is strongly limited by the small scale and high cost. In this paper, we report a simple approach
capable of forming large-area metasurface by anodized aluminum oxide (AAO) template. The Ag nanocylinder
array is deposited through the AAO mask onto the SiO2 substrate by thermal evaporation. Combining such the
18AAO templates with deposition method represents a step toward large-area plasmonic metasurface.
Poster Presentations
2-1 120º Optical Hybrid Based on 3×3 Multimode Interference Coupler
Author: Xue Zheng
Affiliation: Huazhong University of Science and Technology
Abstract: In recent years, new technologies including Internet of Things, artificial intelligence, big data, virtual
reality and cloud computing have driven demands for short-reach optical communications. Coherent optical
detection system has been widely implemented to satisfy the growing needs for next-generation high capacity
information transmission, thanks to its high receiver sensitivity, excellent spectral efficiency and digital signal
processing functionality to compensate several kinds of transmission impairments, such as chromatic dispersion
and polarization mode dispersion. However, conventional coherent receiver architecture based on 90° optical
hybrid cannot be directly deployed in short-reach links due to its high cost and complexity. Therefore, the
scheme of using 120° optical hybrid with single-ended detection is proposed to overcome the above issues in
order to accommodate the requirements of optical access networks. Compared with the 90° optical hybrid, the
120° optical hybrid has a larger working bandwidth and fabrication tolerances, and it is also highly insensitive
to hardware impairments at microwave frequencies. Furthermore, there is no need to use balanced detectors
anymore, as well as crossed waveguides to connect with detectors, making it a more attractive alternative to 90°
optical hybrid. In this paper, we propose and experimentally demonstrate a 120° optical hybrid on the silicon-
on-insulator platform, which can be used for the whole C-band without active controls. The fabricated hybrid
exhibits an excess loss less than 1.5 dB, with phase errors smaller than 7° and imbalances less than 1 dB across
the wavelength range from 1525 to 1575 nm. We believe the proposed hybrid has the potential to implement a
simplifying coherent receiver for coherent receiving systems.
2-2 Facile Synthesis of ZnO/PdSe2 Core-Shell Heterojunction for Efficient Photodetector Application
Author: Zhengtian Shi
Affiliation: National University of Defense Technology
Abstract: Palladium diselenide (PdSe2), a group-10 transition metal dichalcogenide with great optoelectronic
and electrical properties due to unique structure, has gained increasing attention in the scientific community.
Herein, we demonstrate an effective strategy to synthesis of ZnO/PdSe2 core-shell heterojunction nanorod
arrays (HNAs) through a simple two-step method for the first time. A Pd film was deposited on ZnO NAs by an
electron beam evaporation method at first. Then, the selenization process was completed by a chemical vapor
deposition (CVD) method. Furthermore, the photoelectric performances of electrodes based on ZnO NAs,
PdSe2 film and ZnO/PdSe2 core-shell HNAs were investigated, respectively. The ZnO/PdSe2 core-shell HNA
represents better responsitivity with higher photocurrent density (1.3 mA cm-2) comparing to the ZnO NA (0.03
mA cm-2), indicating that the ZnO/PdSe2 samples are more suitable for photoelectric devices. Besides,
19photoelectric performance of this work is better than most of reported commercial ZnO and ZnO composite
nanomaterials.
2-3 Vapor-Phase Growth of CsPbBr3 Microcrystals for Highly Efficient Pure Green Light Emission
Author: Shangui Lan
Affiliation: Huazhong University of Science and Technology
Abstract: All-inorganic lead halide perovskites have been extensively studied in the past several years due to
their superior stability against moisture, oxygen, light, and heat compared with their organic–inorganic
counterparts. CsPbBr3 with suitable band gap and ultrahigh photoluminescence quantum yield is a promising
candidate for pure green emitter in the backlighting display to fill the so-called “green gap.”[1] Here, vapor-
phase growth of CsPbBr3 microspheres is reported for highly efficient pure green light emission.[2] The as-
synthesized microspheres exhibit a stronger photoluminescence (PL) intensity with a photoluminescence
quantum yield of 75% resulting from the lower energy of longitudinal optical phonons revealed by temperature
dependent PL studies. Importantly, with the diameter increasing from 2 to 50 μm the PL peak positions of the
microspheres can be readily tuned from 527 to 539 nm, well filling the so-called “green gap.” The red-shift with
increasing diameter can be ascribed to the reabsorption process during the photon propagation inside the
microspheres. The studies provide a route to improve the photoluminescence quantum yield in all-inorganic
lead halide perovskites, but also suggest an alternative approach to achieve the pure green emission for the
backlighting display.
2-4 Design of secondary lens focusing mechanism for multispectral camera
Author: Rui Wang
Affiliation: University of Chinese Academy of Sciences
Abstract: Due to the influence of mechanical environment, large range temperature change and atmospheric
pressure, the space multispectral camera has a certain amount of defocus in the optical imaging system. In order
to improve the imaging quality of the multispectral camera, if the traditional CAM focusing mechanism is
adopted, it is difficult to meet the requirements of high precision focusing for fast response due to its
20disadvantages such as large volume, poor efficiency and low precision. Therefore, a new focusing mechanism
is designed in this paper, which is composed of rhomboid amplifier large piezoelectric ceramic actuator, flexible
hinge support structure and high-precision capacitance sensor. The mechanism drives the flexible support guide
structure of the parallelogram by means of a rhomboid amplifier large PZT actuator with three points distributed
uniformly and symmetrically at 120°, so that the lens base can move in a straight line along the Z direction. The
high precision capacitance sensor is used as the feedback element to ensure the focusing accuracy of the
mechanism reaches nanometer level. The test results show that the focusing range of this mechanism is
±21.91um, the focusing speed is 438um/s, the focusing precision is 50nm and the tilt error is 1".
2-5 Study on MoS2-SiO2 Nanofilms Prepared by Sol-Gel Method
Author: Jianan Xie
Affiliation: Xi'an University of Technology
Abstract: Two-dimensional MoS2 materials with structures like graphene have become hot topics of research
in recent years, due to their unique physical and chemical properties. The sol-gel method of preparation of
materials is mild and simple. Especially, the uniformity of the reactants at the molecular level cannot be achieved
within a short period of time by other methods. The MoS2-SiO2 composite materials were prepared by a sol-
gel method. The results of confocal microscopy, Raman spectroscopy, transmission electron microscopy, and
X-ray photoelectron spectroscopy showed that the samples prepared in this study contained MoS2 and the
surface of the film was not cracked.
2-6 A Synchronous Control System Designed for Underwater Single-photon Range-gated Imaging Based
on FPGA
Author: Peng Zhou
Affiliation: CAS Key laboratory of Space Precision Measurement Technology, Chinese Academic of Sciences
Abstract: Single-photon imaging technique is a new type of light detection and ranging (LIDAR) technology
used for weak signal detection which has a high sensitivity up to single-photon energy level. It has a broad
prospect of application in the field of underwater imaging. Range-gated technique has been proved to be
effective in reducing the backscattering noise and improving the signal-to-noise ratio (SNR) during the data
acquisition stage. The range-gated synchronous control system is a key component of the underwater single-
photon imaging system. At present, most range-gated synchronous control systems have the defects of low
stepping regulation precision and narrow dynamic regulating range. This paper designs a novel range-gated
synchronous control system which has both a wide dynamic regulating range and a high stepping regulation
precision of gating distance. It is composed of a coarse regulation part and a fine regulation part which are both
based on the field programmable gate array (FPGA). The simulation results show that the dynamic range of the
system’s gated distance can meet the requirement of imaging as far as 7km, and the stepping regulation precision
can reach as high as 39ps, with the gate width adjustable. The system designed in this paper guarantees a high
SNR data acquisition and has a strong adaptability under various distance scenarios along with extra advantages
of lower cost, smaller volume and lighter weight. These features will make a great improvement in the crypticity
and portability of the whole underwater single-photon imaging system.
212-7 LED Plant Lighting System Design Based on Improved Pigeon-Inspired Optimization Algorithm
Author: Zhenxing Ming
Affiliation: Hubei University of Technology
Abstract: With the rapid development of modern agriculture, LEDs as artificial light sources are playing an
increasingly important role in modern agriculture. However, the uneven lighting of LEDs will cause the uneven
quality of agricultural products. For requirements of plant light source on highly uniform illumination
distribution, we put up an improved Pigeon-Inspired Optimization algorithm to design uniform light of the LED
array. Using this method, we designed four different shapes of LED arrays. Through optimizations on MATLAB
and simulation analysis on optical software TracePro, we obtained the illumination uniformity of 91.03%,
91.64%, and 92.89% for hexagonal, circular, and rectangular LED arrays, respectively, and the illumination
uniformity of freely arranged LED array is up to 93.64%. The results show that LED arrays with near-optimal
illumination uniformity on the target plane were obtained by this method. In addition, based on these LED arrays
obtained, we investigated the relationship between the uniformity of the target plane and the vertical distance
of the LED array. It is concluded that as the vertical distance increases, the illumination uniformity of the target
plane increases, but the average illumination value decreases. The improved algorithm proposed in this paper
lay a solid foundation for the uniform lighting design of LEDs.
2-8 Effect of Laser Rust Removalon Surface Roughness of 3Cr2Mo Die Steel
Author: Shiguang Liu
Affiliation: Qingdao University of Technology
Abstract: In order to extend the service life of injection mold, the use of laser rust removal was used to repair
the surface quality of mold steel in this paper. The surface corrosion of mold steel was removed by using the
laser dry cleaning method, then the surface roughness was restored to the initial state to meet the performance
requirements of manufacturing. By analyzing the experimental results, the influence of laser energy density,
spot overlap rate and scanning times on improving the surface quality of corroded area was obtained. It was
shown that when the laser energy density, spot overlap rate and scanning times is 26 J/cm2, 18% and 3 times
respectively, the optimum surface roughness of Sa2.32μm can be obtained, which meets the production
requirements. Compared with traditional rust removal methods, the laser rust removal of the mold surfaces
deserves more extensive research and application due to its advantages of high efficiency, precision and
environmentally friendly.
2-9 Research on spectral combining technology of multi-single emitter diode laser based on composite
grating
Author: Tianze Zhao
Affiliation: Beijing University of Technology
Abstract: In order to solve the problem of low power and poor beam quality in the processing and application
of single emitter diode lasers. A multi-single emitter diode laser spectral combined light source with continuous
22output power of 60W and brightness of 19.67MW/ (sr · cm2) was developed by using the method of spectral
beam combining. The beam quality of the fast axis is 0.49mm · mrad and the slow axis is 4.45mm · mrad. The
beam quality is basically consistent with that of single emitter diode lasers, and the photoelectric conversion
efficiency is 42%.We can improve the laser power and brightness greatly on the premise of maintaining the
original beam quality of the single emitter by beam shaping, so that the single emitter diode lasers light source
can also be widely used in the field of material processing.
2-10 Study on Heat dissipation of VCSEL Array with High Heat Flux
Author: Xu Liu
Affiliation: Beijing University of Technology
Abstract: The thermal characteristics of high power VCSEL arrays have a big impact on its performance. The
key to solve the thermal problem is to design a reasonable heat dissipation system, which was designed by the
method of finite element analysis, including the excessive heat sink of diamond film with thermal conductivity
of 1800W/ (m·K) and thickness of 4mm and the micro-channel heat sink with hydraulic diameter of 7.5mm.
The heat dissipation effect is improved by adding diamond excessive heat sink and micro-channel heat sink.
The VCSEL array, which size is 5mm×5mm and central wavelength is 980nm, was taken as the object to
research its heat generation and heat transfer principle. The VCSEL array with the heating power density of
2×105W/m2 can work normally. The results provide a chance to the next step for a higher-power VCSEL array.
2-11 Analysis and design of a square-law detector based on multiplier for high linearity radiometer
Author: Shuai Dong
Affiliation: Key Laboratory of Microwave Remote Sensing, Chinese Academy of Sciences
Abstract: Radiometers are used in a various number of measurements applications. The output detector is the
main element in the radiometer which determines its linearity and dynamic range. In this paper, the square-law
detection principle of Schottky diode and multiplier is introduced. The multiplication detection module and the
amplifer-filter circuits are designed. The multiplication detector takes the analog multiplier as the core, and the
differential circuit is used at the signal input. The output linearity of 0.99999 is achieved in the bandwidth of 50
MHz ~ 2GHz and the dynamic range of -16dBm ~ 4dBm. Compared with the diode detector, the multiplication
detector has the advantages of large effective bandwidth, wide dynamic range, high linearity and good stability.
2-12 Study on the Wigner distribution function of semiconductor laser
Author: Jing Li
Affiliation: Beijing University of Technology
Abstract: In order to further study the beam characteristics of semiconductor laser, the partial coherence of
semiconductor laser is described by Wigner distribution function. A method for measuring the Wigner
distribution function of semiconductor laser is proposed. Two focusing mirrors are used. The first focusing
mirror is used to measure the Rayleigh length of semiconductor laser, and the second focusing mirror has the
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