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arXiv · 1901.11044

Magneto-photoluminescence of exciton Rydberg states in monolayer WSe$_2$

Erfu Liu·Jeremiah van Baren·Takashi Taniguchi·Kenji Watanabe·Yia-Chung Chang·Chun Hung Lui
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Abstract

Monolayer WSe$_2$ hosts a series of exciton Rydberg states denoted by the principal quantum number n = 1, 2, 3, etc. While most research focuses on their absorption properties, their optical emission is also important but much less studied. Here we measure the photoluminescence from the 1s - 5s exciton Rydberg states in ultraclean monolayer WSe$_2$ encapsulated by boron nitride under magnetic fields from -31 T to 31 T. The exciton Rydberg states exhibit similar Zeeman shifts but distinct diamagnetic shifts from each other. From their luminescence spectra, Zeeman and diamagnetic shifts, we deduce the binding energies, g-factors and radii of the 1s - 4s exciton states. Our results are consistent with theoretical predictions and results from prior magneto-reflection experiments.

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Erfu Liu, Jeremiah van Baren, Takashi Taniguchi, Kenji Watanabe, Yia-Chung Chang, Chun Hung Lui. 2019-01-30. Magneto-photoluminescence of exciton Rydberg states in monolayer WSe$_2$. https://doi.org/10.1103/physrevb.99.205420

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