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arXiv · 2103.07962

Temperature-dependent electronic ground state charge transfer in van der Waals heterostructures

Soohyung Park·Haiyuan Wang·Thorsten Schultz·Dongguen Shin·Ruslan Ovsyannikov·Marios Zacharias·Dmitrii Maksimov·Matthias Meissner·Yuri Hasegawa·Takuma Yamaguchi·Satoshi Kera·Areej Aljarb·Mariam Hakami·Lain-Jong Li·Vincent Tung·Patrick Amsalem·Mariana Rossi·Norbert Koch
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Abstract

Electronic charge rearrangement between components of a heterostructure is the fundamental principle to reach the electronic ground state. It is acknowledged that the density of states distribution of the components governs the amount of charge transfer, but a notable dependence on temperature has not yet been considered, particularly for weakly interacting systems. Here, we experimentally observe that the amount of ground state charge transfer in a van der Waals heterostructure formed by monolayer MoS2 sandwiched between graphite and a molecular electron acceptor layer increases by a factor of three when going from 7 K to room temperature. State-of-the-art electronic structure calculations of the full heterostructure that account for nuclear thermal fluctuations reveal intra-component electron-phonon coupling and inter-component electronic coupling as the key factors determining the amount of charge transfer. This conclusion is rationalized by a model applicable to multi-component van der Waals heterostructures.

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Soohyung Park, Haiyuan Wang, Thorsten Schultz, Dongguen Shin, Ruslan Ovsyannikov, Marios Zacharias, Dmitrii Maksimov, Matthias Meissner, Yuri Hasegawa, Takuma Yamaguchi, Satoshi Kera, Areej Aljarb, Mariam Hakami, Lain-Jong Li, Vincent Tung, Patrick Amsalem, Mariana Rossi, Norbert Koch. 2021-03-14. Temperature-dependent electronic ground state charge transfer in van der Waals heterostructures. https://arxiv.org/abs/2103.07962

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