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arXiv · 1612.02867

Brightening of dark excitons in monolayers of semiconducting transition metal dichalcogenides

M. R. Molas·C. Faugeras·A. O. Slobodeniuk·K. Nogajewski·M. Bartos·D. M. Basko·M. Potemski
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Abstract

We present low temperature magneto-photoluminescence experiments which demonstrate the brightening of dark excitons by an in-plane magnetic field $B$ applied to monolayers of different semiconducting transition metal dichalcogenides. For both WSe$_2$ and WS$_2$ monolayers, the dark exciton emission is observed at $\sim$50 meV below the bright exciton peak and displays a characteristic doublet structure which intensity is growing with $B^2$, while no magnetic field induced emission peaks appear for MoSe$_2$ monolayer. Our experiments also show that the MoS$_2$ monolayer has a dark exciton ground state with a dark-bright exciton splitting energy of $\sim$100 meV.

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M. R. Molas, C. Faugeras, A. O. Slobodeniuk, K. Nogajewski, M. Bartos, D. M. Basko, M. Potemski. 2016-12-08. Brightening of dark excitons in monolayers of semiconducting transition metal dichalcogenides. https://doi.org/10.1088/2053-1583%2Faa5521

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