Staff Achievements 2025

Prof YAO Jin, Research Assistant Professor under the research group of Prof Din-ping Tsai, has won the Best Paper Award at the 11^th International Conference on Surface Plasmon Photonics. The winning paper is titled “Nonlocal meta-lens for spin-multiplexing focusing and imaging”.

The International Conference on Surface Plasmon Photonics (SPP) is a biennial, independent, and non-profit conference series widely regarded as the premier event in the field of plasmonics. The conference addresses both fundamental aspects and practical applications of plasmonics.

Prof Gengbo WU (Assistant Professor of EE), Dr Yuansong ZENG (Research Fellow, SKLTMW), and Dr Jin CHEN (Postdoc, SKLTMW) have published a paper in the top journal – Nature, on 14 May 2025. The paper titled “Bulk–spatiotemporal vortex correspondence in gyromagnetic zero-index media” is a collaborative work with scholars coming from The Hong Kong University of Science and Technology, Fudan University, Wuhan University, Shenzhen University, and University of Southampton.

This paper can be found at Nature. To give you a glimpse of the research work, here is a brief introduction: Here we experimentally realize gyromagnetic double-zero-index metamaterials possessing both double-zero-index features and non-reciprocal hallmarks. We discover and demonstrate that a spatiotemporal reflection vortex singularity is always anchored to the Dirac point of the metamaterial, with the vortex charge being determined by the topological invariant leap across the phase transition. This establishes a unique bulk–spatiotemporal vortex correspondence that extends the protected boundary effects into the time domain and characterizes topological phase-transition points. Based on this correspondence, we propose and experimentally demonstrate a mechanism to deterministically generate optical spatiotemporal vortex pulses with firmly fixed central frequency and momentum. Our findings uncover connections between zero-refractive-index photonics, topological photonics and singular optics, which might enable the manipulation of space-time topological light fields using the inherent topology of extreme-parameter metamaterials.

Dr FAN Yubin, Postdoc under the supervision of Prof Din-ping Tsai, has won the Best Paper Award at Meta Photonics: Design, Fabrication, Characterization, and Applications (META) - Optics & Photonics International Congress 2025. The winning paper is titled “Metalens array for high-dimensional quantum random number generator”.

The Optics and Photonics International Congress (OPIC), co-organized with the Optics and Photonics International Exhibition (OPIE), brings together researchers and developers from around the world to discuss the science and industry of optics and photonics. OPIC currently comprises Specialized International Conferences covering a broad range of fields: lasers, biomedicine, nano-photonics, meta-surface, optical measurement, optical manipulation, x-ray optics, IoT, display and lighting, high energy density science, power transmission, space and earth science, and agriculture photonics.

Prof Chaoliang Tan (Associate Professor of EE), Prof Andy Chan (Associate Professor of EE), Dr Jiajia Zha (Postdoc), Mr Haoxin Huang (PhD student), and Dr Yunpeng Xia (PhD graduate 2024), have published a paper in the top journal – Nature Communications, on 24 April 2025. The paper titled “In-sensor compressing via programmable optoelectronic sensors based on van der Waals heterostructures for intelligent machine vision” is a collaborative work with scholars coming from CHEM and MSE Department of CityUHK, The University of Hong Kong, The Chinese University of Hong Kong, The Hong Kong University of Science and Technology, The Hong Kong Polytechnic University, Southern University of Science and Technology, Shenzhen, Shenzhen University, and Shenzhen Technology University.

This Nature Communications paper can be found at https://www.nature.com/articles/s41467-025-59104-7. To give you a glimpse of the research work, here is a quote from the abstract: 

Here we demonstrate a programmable two-dimensional (2D) heterostructure-based optoelectronic sensor integrating sensing, memory, and computation for in-sensor data compression. Our 2D sensor captured and memorized/encoded optical signals, leading to in-device snapshot compression of dynamic videos and three-dimensional spectral data with a compression ratio of 8:1. The reconstruction quality, indicated by a peak signal-to-noise ratio value of 15.81 dB, is comparable to the 16.21 dB achieved through software. Meanwhile, the compressed action videos (in the form of 2D images) preserve all semantic information and can be accurately classified using in-sensor convolution without decompression, achieving accuracy on par with uncompressed videos (93.18% vs 83.43%). Our 2D optoelectronic sensors promote the development of efficient intelligent vision systems at the edge.

EE teams achieved remarkable results at the 50^th International Exhibition of Inventions of Geneva (IEIG), winning 5 awards, including one Gold Medal with Congratulations of the Jury, one Gold Medal, and three Silver Medals. The results are encouraging and demonstrate the international recognition of EE's research and scientific achievements.

The exhibition is the world’s most important event exclusively dedicated to inventions. It offers a unique opportunity for universities, inventors and researchers, industrial and commercial companies, associations, private and state organisms and institutions to present the results of their research, their inventions, and their new products. The 50^th IEIG, held from 9 to 13 April in Geneva, Switzerland, featured more than 1,000 inventions from 42 countries and regions around the world.  

More details about this good news can be found at CityU NewsCentre.

Prof Hong Yan (Chair Professor of EE), Mr Zelin Li (PhD student), and Dr Jianfeng Cao (PhD graduate in 2021), have published a paper in the top journal – Nature Communications, on 18 April 2025. The paper titled "Cell lineage-resolved embryonic morphological map reveals signaling associated with cell fate and size asymmetry" is a collaborative work with scholars coming from Peking University and Hong Kong Baptist University.

This Nature Communications paper can be found at Nature Communications. To give you a glimpse of the research work, here is a quote from the abstract: Here we present a comprehensive real-time cellular map that covers over 95% of the cells formed during Caenorhabditis elegans embryogenesis, featuring nearly 400,000 3D cell regions. This map includes information on each cell’s identity, lineage, fate, shape, volume, surface area, contact area, and gene expression profiles, all accessible through our user-friendly software and website. Our map allows for detailed analysis of key developmental processes, including dorsal intercalation, intestinal formation, and muscle assembly. We show how Notch and Wnt signaling pathways, along with mechanical forces from cell interactions, regulate cell fate decisions and size asymmetries. Our findings suggest that repeated Notch signaling drives size disparities in the large excretory cell, which functions like a kidney. This work sets the stage for in-depth studies of the mechanisms controlling cell fate differentiation and morphogenesis.

The research work led by Prof Cheng Wang (Associate Professor) has been awarded China’s Top 10 Advances in Optics in the category of Applied Research which is organized by Chinese Laser Press.

The excellent research outcomes can be found in the journal paper "Integrated lithium niobate microwave photonic processing engine," published in Nature on 28 February 2024 . It is a collaborative work among Prof Wang’s PhD students or graduates, Postdoctoral Fellows, and scholars from CityU Dongguan, Nankai University and The Chinese University of Hong Kong.

You may visit here to learn more about the award and also the research work here. 

The collaborative research team, comprising Prof Din-ping Tsai (Chair Professor of EE), Postdoctoral Fellows of EE, and scholars from Xiamen University, published a paper in the top journal – Nature Communications, on 11 March 2025.

Title: Metasurface enabled high-order differentiator

Authors:

• Prof Din-ping Tsai (Chair Professor of EE, City University of Hong Kong)
• Dr Xiaodong Qiu Postdoctoral Fellow of EE)
• Dr Jingcheng Zhang (Postdoctoral Fellow of EE)
• Dr Yubin Fan (Postdoctoral Fellow of EE)
• Dr Junxiao Zhou (Postdoctoral Fellow of EE)
• Prof Lixiang Chen (Professor of Optics, Department of Physics, Xiamen University)

This Nature Communications paper can be found here. To give you a glimpse of the research work, here is a quote from the abstract: 

Here, drawing on the basic mathematical feature of the Fourier transform, we theoretically propose universal phase-gradient functions of the Pancharatnam-Berry-phase-based meta-device for performing arbitrary order differentiation. The fifth-order optical differentiations for both intensity and phase images are realized in the experiment. More importantly, by exploring this elaborately designed spatial differentiator, we construct another scheme for optical super-resolution and achieve the estimation of the distance between two incoherent point sources within 0.015 of the Rayleigh distance, which thereby provides a potential toolkit for optical alignment in high-precision semiconductor nano-fabrication. Our findings hold promise for image processing, microscopy imaging, and optical super-resolution imaging.

Prof K M Luk, Chair Professor of EE, has been selected to receive the 2025 IEEE AP-S Chen-To Tai Distinguished Educator Award for his significant contributions in education of antenna theory, design and applications. The award will be presented at the 2025 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, which will take place at the Rogers Centre in Ottawa, Canada, in July 2025.

IEEE Antennas and Propagation Society (IEEE AP-S) is recognized as the leading society in the antenna field in the world. The Chen-To Tai Distinguished Educator Award was established in 2000 to recognize the individual who has given outstanding service to education in the field of antennas and propagation, who exemplifies the special humanities of Chen-To Tai, and whose exemplary career in teaching and research represents the highest qualities of service. Prof Luk’s lifelong dedication to teaching and research in the field of antennas and propagation earns him this great achievement.

Professor Derrick Jiang (Assistant Professor of EE) and his research team have been honored with the Y-LOT’s 3rd Hong Kong SciTech Pioneers Award 2023-2024, in recognition of their outstanding dedication and contributions to emerging technologies for electric vehicles.

The award, hosted by Y-LOT Foundation and sponsored by Herson Land and Innovation and Technology Commission (ITC), aims to recognize and celebrate the valuable contributions of outstanding scientists and research teams in the fields of Deep Tech, Biotechnology, Space Science, ESG, and Future Innovation. Prof Jiang is the awardee in the Deep Tech category.