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arXiv · 2303.00363

Overbias photon emission from light-emitting devices based on monolayer transition metal dichalcogenides

Shengyu Shan·Jing Huang·Sotirios Papadopoulos·Ronja Khelifa·Takashi Taniguchi·Kenji Watanabe·Lujun Wang·Lukas Novotny
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Abstract

Tunneling light-emitting devices (LEDs) based on transition metal dichalcogenides (TMDs) and other 2D materials are a new platform for on-chip optoelectronic integration. Some of the physical processes underlying this LED architecture are not fully understood, especially the emission at photon energies higher than the applied electrostatic potential, so-called overbias emission. Here we report overbias emission for potentials that are near half of the optical bandgap energy in TMD-based tunneling LEDs. We show that this emission is not thermal in nature, but consistent with exciton generation via a two-electron coherent tunneling process.

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Shengyu Shan, Jing Huang, Sotirios Papadopoulos, Ronja Khelifa, Takashi Taniguchi, Kenji Watanabe, Lujun Wang, Lukas Novotny. 2023-03-01. Overbias photon emission from light-emitting devices based on monolayer transition metal dichalcogenides. https://arxiv.org/abs/2303.00363

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