Events Calendar

ECE PhD Prospectus Defense: Hriteshwar Talukder

Title: NON-HERMITIAN TOPOLOGICAL PHOTONIC CRYSTALS FOR LIGHT SENSING

Presenter: Hriteshwar Talukder

Advisor: Professor Roberto Paiella

Chair: Professor Anna Swan

Committee: Professor Anna Swan, Professor Milos Popovic, Professor Tianyu Wang, and Professor Roberto Paiella

Google Scholar Link: https://scholar.google.com/citations?user=yPwKhn8AAAAJ&hl=en

Abstract: Non-Hermitian topological photonic systems have emerged as a powerful platform for realizing wave phenomena with no counterparts in conventional Hermitian physics, including exceptional points, topological band transitions, and the non-Hermitian skin effect (NHSE). This project aims to develop a novel class of such systems and to demonstrate both their fundamental properties and their optoelectronic device potential. Specifically, we will design, fabricate, and characterize silicon photonic crystal slabs operating at wavelengths within the material absorption band, consisting of line-connected nanoparticle arrays with independent electrical readout for each row of unit cells. These structures can support engineered non-Hermitian topological modes that localize at sample edges or at domain boundaries between adjacent lattice sections. Their spatial field distributions and spectral dispersions will be probed through wavelength-, angle-, and polarization-resolved photocurrent measurements, enabling line-by-line mapping of guided resonances. This measurement approach provides a uniquely sensitive platform for experimentally demonstrating the reciprocal-space Su–Schrieffer–Heeger (SSH) model, the NHSE, and the breakdown of conventional bulk–boundary correspondence. Simultaneously, the same properties open new avenues for the design of highly miniaturized photodetectors exhibiting unconventional and customizable angular and spectral responses.