About us
We are a theoretical research group at the School of Electrical and Electronic Engineering and the Institute for Digital Molecular Analytics and Science at Nanyang Technological University, Singapore. The group is lead by Assistant Professor Matthew R. Foreman.
Our research focuses on optical and plasmonic sensing, polarisation sensitive imaging, disordered media and electromagnetic theory. More information on some of our past and present projects can be found by visiting our Research pages.
Recent news
We are hiring! Three Research Fellow positions available
21 Sep 2023: We currently have three open research fellow positions in the Optical Theory Group, to support new and ongoing research efforts in the areas of modelling of complex optical networks, informatics in digital molecular assays and computational imaging. Click the links to get more information and apply. Feel free to get in touch for more information.
New Masters Student - Shiqi Tang
16 Aug 2023: We are excited to welcome a new masters student to the group. Shiqi Tang will be joining to work on modelling complex optical networks and their optical properties.
New Research Fellow - Aswani Natarajan
14 Aug 2023: The OTG team is growing! We welcome Dr Aswani Natarajan as the latest addition to the group. She will be joining our efforts at IDMxS working on electromagnetic modelling of optical imaging and sensing systems.
Recent publications
Abstract : In this work we present a method for generating random matrices describing electromagnetic scattering from disordered media containing dielectric particles with prescribed single particle scattering characteristics. Resulting scattering matrices automatically satisfy the physical constraints of unitarity, reciprocity and time reversal, whilst also incorporating the polarization properties of electromagnetic waves and scattering anisotropy. Our technique therefore enables statistical study of a variety of polarization phenomena, including depolarization rates and polarization-dependent scattering by chiral particles. In this vein, we perform numerical simulations for media containing isotropic and chiral spherical particles of different sizes for thicknesses ranging from the single to multiple scattering regime and discuss our results, drawing comparisons to established theory.
Abstract : We report sensing of single nanoparticles using disordered metallic nanoisland substrates supporting surface plasmon polaritons (SPPs). Speckle patterns arising from leakage radiation of elastically scattered SPPs provides a unique fingerprint of the scattering microstructure at the sensor surface. Experimental measurements of the speckle decorrelation are presented and shown to enable detection of sorption of individual gold nanoparticles and polystyrene beads. Our approach is verified through bright-field and fluorescence imaging of particles adhering to the nanoisland substrate.
Abstract : We study the polarisation properties of random N×N scattering matrices distributed according to the circular orthogonal ensemble. We interpret 2×2 sub-blocks of the scattering matrix as Jones matrices and study their statistical properties. Using the polar decomposition, we derive probability density functions for retardance and diattenuation from scattering matrices of arbitrary size and in the limit N → ∞.
Funding
Our research is supported by generous funding from:
