Nanoscale Positioning of Single‐Photon Emitters in Atomically Thin WSe₂

Abstract

Single-photon emitters in monolayer WSe2 are created at the nanoscale gap between two single-crystalline gold nanorods. The atomically thin semiconductor conforms to the metal nanostructure and is bent at the position of the gap. The induced strain leads to the formation of a localized potential well inside the gap. Single-photon emitters are localized there with a precision better than 140 nm.

Single photon emission from deep-level defects in monolayerWSe2

“…Spatially, it was known that the discrete lines occur often at the edges of flakes and the regions of high strain gradient. 2,[9][10][11] We find that for most samples the studied 2D exciton peaks disappear under an applied pressure of ~ 0.6−1.5 GPa at the first cycle of in situ pressure-changing process. After releasing the pressure to zero, a remarkable change of PL lineshape is observed, as typically shown in Fig.…”

Single-photon emitters in GaSe

“…However, in contrast to conventional semiconductors such as Silicon or GaAs, the extraordinary mechanical properties of 2D materials allows for applying strain of a few percent and strong nanoscale bending. Indeed, the origin of the quantum emission in atomically thin WSe 2 has been related to strain-induced local confinement potentials, which trap free excitons [5, 21,22]. Here, we report on the discovery of singlephoton emitters in GaSe.…”

Spatio-Temporal Dynamics of Carrier Capture Processes: Simulation of Optical Signals

“…Carrier capture processes occur frequently in several semiconductor structures, e.g., scattering of carriers from the wetting layer to quantum dots [1][2][3][4][5][6], from a quantum wire to the embedded quantum dot [7][8][9], or from monolayers of transition metal dichalcogenides (TMDCs) to discrete states created by strain effects [10,11]. All those processes happen on subpicosecond time scales and on nanometric length scales and therefore are of genuinely quantum mechanical nature.…”