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arXiv · 2207.00452

The impact of valley profile on the mobility and Kerr rotation of transition metal dichalcogenides

Thibault Sohier·Pedro M. M. C. de Melo·Zeila Zanolli·Matthieu Jean Verstraete
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Abstract

The transport and optical properties of semiconducting transition metal dichalcogenides around room temperature are dictated by electron-phonon scattering mechanisms within a complex, spin-textured and multi-valley electronic landscape. The relative positions of the valleys are critical, yet they are sensitive to external parameters and very difficult to determine directly. We propose a first-principle model as a function valley positions to calculate carrier mobility and Kerr rotation angles. The model brings valuable insights, as well as quantitative predictions of macroscopic properties for a wide range of carrier density. The doping-dependant mobility displays a characteristic peak, the height depending on the position of the valleys. The Kerr rotation signal is enhanced when same spin-valleys are aligned, and quenched when opposite spin-valleys are populated. We provide guidelines to optimize these quantities with respect to experimental parameters, as well as the theoretical support for \emph{in situ} characterization of the valley positions.

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Thibault Sohier, Pedro M. M. C. de Melo, Zeila Zanolli, Matthieu Jean Verstraete. 2022-10-24. The impact of valley profile on the mobility and Kerr rotation of transition metal dichalcogenides. https://doi.org/10.1088/2053-1583%2Facb21c

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