Effect of spin-dependent tunneling in a MoSe$_2$/Cr$_2$Ge$_2$Te$_6$ van der Waals heterostructure on exciton and trion emission

Annika Bergmann; Swarup Deb; Klaus Zollner; Veronika Schneidt; Mustafa Hemaid; Kenji Watanabe; Takashi Taniguchi; Rico Schwartz; Jaroslav Fabian; Tobias Korn

arXiv · 2407.11603

Effect of spin-dependent tunneling in a MoSe$_2$/Cr$_2$Ge$_2$Te$_6$ van der Waals heterostructure on exciton and trion emission

Annika Bergmann·Swarup Deb·Klaus Zollner·Veronika Schneidt·Mustafa Hemaid·Kenji Watanabe·Takashi Taniguchi·Rico Schwartz·Jaroslav Fabian·Tobias Korn

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Abstract

We study van der Waals heterostructures consisting of monolayer MoSe$_2$ and few-layer Cr$_2$Ge$_2$Te$_6$ fully encapsulated in hexagonal Boron Nitride using low-temperature photoluminescence and polar magneto-optic Kerr effect measurements. Photoluminescence characterization reveals a partial quenching and a change of the exciton-trion emission ratio in the heterostructure as compared to the isolated MoSe$_2$ monolayer. Under circularly polarized excitation, we find that the exciton-trion emission ratio depends on the relative orientation of excitation helicity and Cr$_2$Ge$_2$Te$_6$ magnetization, even though the photoluminescence emission itself is unpolarized. This observation hints at an ultrafast, spin-dependent interlayer charge transfer that competes with exciton and trion formation and recombination.

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Annika Bergmann, Swarup Deb, Klaus Zollner, Veronika Schneidt, Mustafa Hemaid, Kenji Watanabe, Takashi Taniguchi, Rico Schwartz, Jaroslav Fabian, Tobias Korn. 2024-07-16. Effect of spin-dependent tunneling in a MoSe$_2$/Cr$_2$Ge$_2$Te$_6$ van der Waals heterostructure on exciton and trion emission. https://arxiv.org/abs/2407.11603

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