Events

Date: 19 March 2026   Time: 11:00 - 12:00     

Location: Queens Building QB 215 + Online

Seminar Online Link

Synopsis

Light-matter interactions can be highly controlled via nanoscale structures, hundreds of times thinner than human hair. Indeed, a single layer of designed and engineered subwavelength nanostructures, so-called metasurfaces, can resonantly couple to incident light and manipulate its behaviour on demand. Indeed, metasurfaces are a valuable tool for enhancing nanoscale light-matter interactions by exciting both optically induced electric and magnetic Mie resonances, which play a crucial role in modern nanophotonics. As a result, metasurfaces can reproduce the functions of bulk optics and, on occasions, can offer new functionalities that are not possible with conventional diffractive optics.

In the first half of the Seminar, Rahmani will review the research activities at the Advanced Optics and Photonics Group at Nottingham Trent University on light-matter interaction with nanoparticles. He will discuss the group's activities on employing metallic, dielectric and semiconductor metasurfaces to control light intensity, frequency and propagation direction. He will particularly discuss applications of reconfigurable metasurfaces for generating a new display technology. In the 2nd half of the Seminar, Xu will discuss the group approaches to designing high-quality metasurfaces, particularly for nonlinear imaging. He shares recent results on converting infrared images to visible with high quality, leading to possibilities for new types of all-optical infrared imaging devices using metasurfaces. He will explain how resonant metasurfaces offer new approaches for non-destructive and rapid quantitative detection of trace biological and chemical substances.

Biography

Prof. Mohsen Rahmani received his PhD from the National University of Singapore in 2013, followed by a postdoc fellowship at Imperial College London and the Australian Research Council Early Career Fellowship at the Australian National University. In 2020, he moved to NTU as a Royal Society Wolfson Fellow, followed by the UK Research and Innovation Future Leaders Fellowship, and a recent ERC Consolidator Grant. His research activities span over light-matter interactions with various subwavelength nanoparticles for applications in flat optics, near-infrared imaging, bio-sensing, etc.

Associate Prof. Dr Lei Xu obtained his PhD (2014) in Optics from Nankai University, China. Since then, he has been performing research and engineering activities in different universities: Nankai University, The Australian National University and the University of New South Wales. His re-search interests are linear and nonlinear nanophotonics, optoelectronics meta-devices, and bio-photonics. He served as deputy chair and chair of the IEEE Nanotechnology chapter across the UK & Ireland in 2022-23 and 2024, respectively.