Site-Controlled Quantum Emitters in Monolayer MoSe₂

Abstract

Atomically thin semiconductors provide a highly attractive platform for quantum emitters (QEs): They can be combined with arbitrary substrates, can be spatially aligned with photonic structures, and can be electrically driven. All QEs reported to date in these materials have, however, relied on nominally spin-forbidden transitions, with radiative rates falling substantially below those of other solid-state QE systems. Here we employ strain confinement in monolayer MoSe2 to produce engineered QEs, as confirmed in photon antibunching measurements. We discuss spin-allowed versus spin-forbidden transitions based on magneto- and time-resolved photoluminescence measurements. We calculate a radiative rate for spin-allowed quantum emission greater than 1 ns–1, which exceeds reported radiative rates of WSe2 QEs by 2 orders of magnitude.

Tuning the Optical Properties of an MoSe$_2$ Monolayer Using Nanoscale Plasmonic Antennas

“…The integrated intensity consistently shows a dip at the position of nanostructures. The spectrum recorded on the nanoantenna in Figure 4a tructures [72,73]. These transitions possibly stem from locally trapped excitons, whose origin is often attributed to defects [74], strain fields [71], and the gradient in the dielectric environment [68].…”

Nanomaterials for Quantum Information Science and Engineering

“…Emitters in 2D TMDs are interesting in this application given the ease of tunability, control (via strain and electric fields), and integration with nanophotonic elements. However, the purity (0.05 < g 2 (0) < 0.3) and radiative lifetimes (typically >1 ns) are currently behind III-V eQDs [448,454,456,459,460,544] . For both hBN and TMDs, it is crucial to better understand the physics and chemistry of emissive defect states.…”

“…Localized strain is typically created by transferring TMD flakes onto arrays of patterned nanostructures [454,464,465] . Gold nanostars (AuNSs) with tip radii <5 nm dispersed on the surface of 1L-WSe2 were used by Peng et al to create strain-localized emitters [455] .…”

A low cost plasmonic platform for photon emission engineering of two dimensional semiconductors

“…We observed a PL enhancement of eight to ten times which was explained using FDTD simulations and higher excitonic spectral weight. Other than the traditional avenues of plasmon enhanced optoelectronics [9], our platform would enable unique applications to deterministic strain and dielectric screening based periodic modulation of the optical response of 2D semiconductors [41], including the development of quantum emitter arrays [42,43], exciton funneling based devices [44][45][46][47] and the observation of dark excitons [48,49]. Acknowledgement-A.K.S acknowledges financial support from Industrial Research and Consultancy Center…”