Nanobubble induced formation of quantum emitters in monolayer semiconductors

TL;DR

This paper demonstrates that nanobubbles in monolayer semiconductors can be deliberately used to induce quantum emitters, advancing the control of localized excitons for nanophotonics and quantum technologies.

Contribution

It reveals that nanobubbles, rather than dopants or defects, can be intentionally created to generate quantum emitters in monolayer semiconductors, providing a new fabrication method.

Findings

Quantum emitters are correlated with nanobubbles and wrinkles.

Hot stamping prevents formation of quantum emitters.

Nanobubbles enable deterministic quantum emitter formation.

Abstract

The recent discovery of exciton quantum emitters in transition metal dichalcogenides (TMDCs) has triggered renewed interest of localized excitons in low-dimensional systems. Open questions remain about the microscopic origin previously attributed to dopants and/or defects as well as strain potentials. Here we show that the quantum emitters can be deliberately induced by nanobubble formation in WSe2 and BN/WSe2 heterostructures. Correlations of atomic-force microscope and hyperspectral photoluminescence images reveal that the origin of quantum emitters and trion disorder is extrinsic and related to 10 nm tall nanobubbles and 70 nm tall wrinkles, respectively. We further demonstrate that hot stamping results in the absence of 0D quantum emitters and trion disorder. The demonstrated technique is useful for advances in nanolasers and deterministic formation of cavity-QED systems in monolayer materials.