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arXiv · 2106.07805

Scattering between minivalleys in a moir\'e material

Petar Tomić·Peter Rickhaus·Aitor Garcia-Ruiz·Giulia Zheng·Elías Portolés·Vladimir Fal'ko·Kenji Watanabe·Takashi Taniguchi·Klaus Ensslin·Thomas Ihn·Folkert K. de Vries
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Abstract

A unique feature of the complex band structures of moir\'e materials is the presence of minivalleys, their hybridization, and scattering between them. Here we investigate magneto-transport oscillations caused by scattering between minivalleys - a phenomenon analogous to magneto-intersubband oscillations - in a twisted double bilayer graphene sample with a twist angle of 1.94{\deg}. We study and discuss the potential scattering mechanisms and find an electron-phonon mechanism and valley conserving scattering to be likely. Finally, we discuss the relevance of our findings for different materials and twist angles.

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Petar Tomić, Peter Rickhaus, Aitor Garcia-Ruiz, Giulia Zheng, Elías Portolés, Vladimir Fal'ko, Kenji Watanabe, Takashi Taniguchi, Klaus Ensslin, Thomas Ihn, Folkert K. de Vries. 2021-06-14. Scattering between minivalleys in a moir\'e material. https://doi.org/10.1103/physrevlett.128.057702

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