Near-Perfect Absorption of Light by Coherent Plasmon-Exciton States

Nano Lett. 2021 May 12;21(9):3864-3870. doi: 10.1021/acs.nanolett.1c00389. Epub 2021 May 3.

Abstract

We experimentally demonstrate and theoretically study the formation of coherent plasmon-exciton states which exhibit absorption of >90% of the incident light (at resonance) and cancellation of absorption. These coherent states result from the interaction between a material supporting an electronic excitation and a plasmonic structure capable of (near) perfect absorption of light. We illustrate the potential implications of these coherent states by measuring the charge separation attainable after photoexcitation. Our study opens the prospect for realizing devices that exploit coherent effects in applications.

Keywords: Plasmonics; hot-charge carriers; strong coupling; ultrafast spectroscopy.