Topological Spaser in a Non-uniform Field

ORAL

Abstract

We propose a nanospaser made of an achiral plasmonic-metal nanodisc and a two-dimensional
chiral gain medium, e.g., a monolayer transition-metal dichalcogenide (TMDC). Such a gain medium can pumped by circularly-polarized radiation into a valley-polarized (topologically-charged) state where the population-inversion of the K and Kvalleys may be different. Each valley's population inversion independently feeds a chiral spasing mode of the nanodisk. There are two such modes that carry opposite topological charges; they do not compete with or cross-talk to each other, and are highly independent. The local fields of these modes rotate in time in opposite directions and are highly nonuniform in space.

*1. Office of Naval Research (DOD); N000-14-17-1-2588
2. Emory University, subcontracted by the National Science Foundation (NSF); T883032 is the subaward number; the Federal Award no. is EFMA-1741691
3. Department of Energy (DOE); DE-FG02-01ER15213
4. Department of Energy (DOE); DE-SC0007043
5. University of Central Florida, subcontracted by the Air Force Office of Scientific Research (AFOSR); 24086151 is the subaward number; the Federal Award no. is FA9550-15-1-0037

Presenters

  • Rupesh Ghimire

    • Department of Physics and Center of Nano Optics, Georgia State University

Authors

  • Rupesh Ghimire

    • Department of Physics and Center of Nano Optics, Georgia State University
  • Jhih-Sheng Wu

    • Department of Physics and Center of Nano Optics, Georgia State University
  • Vadym Apalkov

    • Department of Physics and Center of Nano Optics, Georgia State University
    • Georgia State University
  • Mark I Stockman

    • Department of Physics and Center of Nano Optics, Georgia State University
    • Georgia State University