Publications [#362479] of Henry Everitt

Papers Published

1. Yang, F; Prasad, CS; Li, W; Lach, R; Everitt, HO; Naik, GV, Non-Hermitian metasurface with non-trivial topology, Nanophotonics, vol. 11 no. 6 (February, 2022), pp. 1159-1165 [doi]
   (last updated on 2025/11/07)

   Abstract:
   The synergy between topology and non-Hermiticity in photonics holds immense potential for next-generation optical devices that are robust against defects. However, most demonstrations of non-Hermitian and topological photonics have been limited to super-wavelength scales due to increased radiative losses at the deep-subwavelength scale. By carefully designing radiative losses at the nanoscale, we demonstrate a non-Hermitian plasmonic-dielectric metasurface in the visible with non-trivial topology. The metasurface is based on a fourth order passive parity-time symmetric system. The designed device exhibits an exceptional concentric ring in its momentum space and is described by a Hamiltonian with a non-Hermitian Z 3 ${\mathbb{Z}}_{3}$ topological invariant of V = -1. Fabricated devices are characterized using Fourier-space imaging for single-shot k-space measurements. Our results demonstrate a way to combine topology and non-Hermitian nanophotonics for designing robust devices with novel functionalities.