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arXiv · 1803.04067

Valley-selective exciton bistability in a suspended monolayer semiconductor

Hongchao Xie·Shengwei Jiang·Jie Shan·Kin Fai Mak
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Abstract

We demonstrate robust power- and wavelength-dependent optical bistability in fully suspended monolayers of WSe2 near the exciton resonance. Bistability has been achieved under continuous-wave optical excitation at an intensity level of 10^3 W/cm^2. The observed bistability is originated from a photo-thermal mechanism, which provides both optical nonlinearity and passive feedback, two essential elements for optical bistability. Under a finite magnetic field, the exciton bistability becomes helicity dependent, which enables repeatable switching of light purely by its polarization.

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Hongchao Xie, Shengwei Jiang, Jie Shan, Kin Fai Mak. 2018-03-12. Valley-selective exciton bistability in a suspended monolayer semiconductor. https://doi.org/10.1021/acs.nanolett.8b00987

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