Scanning Tunneling Microscope-Induced Excitonic Luminescence of a Two-Dimensional Semiconductor - Archive ouverte HAL Access content directly
Journal Articles Physical Review Letters Year : 2019

Scanning Tunneling Microscope-Induced Excitonic Luminescence of a Two-Dimensional Semiconductor

Abstract

The long sought-after goal of locally and spectroscopically probing the excitons of two-dimensional (2D) semiconductors is attained using a scanning tunneling microscope (STM). Excitonic luminescence from monolayer molybdenum diselenide (MoSe 2) on a transparent conducting substrate is electrically excited in the tunnel junction of an STM under ambient conditions. By comparing the results with photoluminescence measurements, the emission mechanism is identified as the radiative recombination of bright A excitons. STM-induced luminescence is observed at bias voltages as low as those that correspond to the energy of the optical band gap of MoSe 2. The proposed excitation mechanism is resonance energy transfer from the tunneling current to the excitons in the semiconductor, i.e., through virtual photon coupling. Additional mechanisms (e.g., charge injection) may come into play at bias voltages that are higher than the electronic band gap. Photon emission quantum efficiencies of up to 10 −7 photons per electron are obtained, despite the lack of any participating plasmons. Our results demonstrate a new technique for investigating the excitonic and optoelectronic properties of 2D semiconductors and their heterostructures at the nanometer scale.
Fichier principal
Vignette du fichier
PhysRevLett.123.027402.pdf (1.09 Mo) Télécharger le fichier
suppinfo.pdf (671.13 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-02183510 , version 1 (15-07-2019)

Identifiers

Cite

Delphine Pommier, Rémi Bretel, Luis E Parra López, Florentin Fabre, Andrew Mayne, et al.. Scanning Tunneling Microscope-Induced Excitonic Luminescence of a Two-Dimensional Semiconductor. Physical Review Letters, 2019, ⟨10.1103/PhysRevLett.123.027402⟩. ⟨hal-02183510⟩
183 View
594 Download

Altmetric

Share

Gmail Facebook X LinkedIn More