Radiative enhancement of single quantum emitters in WSe2 monolayers using site-controlled metallic nano-pillars

TL;DR

This paper demonstrates a method to enhance and control quantum emitters in WSe2 monolayers using site-controlled plasmonic nano-pillars, enabling improved light emission for quantum technologies.

Contribution

The authors develop a technique to generate and couple quantum emitters in WSe2 to precisely positioned plasmonic nano-pillars, achieving enhanced emission and site control.

Findings

Enhanced spontaneous emission observed

Emitters are effectively coupled to plasmonic modes

Potential for bright, site-controlled quantum light sources

Abstract

Plasmonic nano-structures provides an efficient way to control and enhance the radiative properties of quantum emitters. Coupling these structures to single defects in low-dimensional materials provides a particularly promising material platform to study emitter-plasmon interactions because these emitters are not embedded in a surrounding dielectric. They can therefore approach a near-field plasmonic mode to nanoscale distances, potentially enabling strong light-matter interactions. However, this coupling requires precise alignment of the emitters to the plasmonic mode of the structures, which is particularly difficult to achieve in a site-controlled structure. We present a technique to generate quantum emitters in 2D tungsten diselenide (WSe2) coupled to site-controlled plasmonic nano-pillars. The plasmonic nano-pillars induce strain in the two dimensional material which generates quantum emitters near the high-field region of the plasmonic mode. The electric field of the nano-pillar mode lies close to parallel with the two-dimensional material, and is therefore in the correct orientation to couple to quantum emitters. Interactions between the emitter and plasmonic mode result in an enhanced spontaneous emission and increased brightness. This approach may enable bright site-controlled non-classical light sources for applications in quantum communication and optical quantum computing.