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arXiv · 2305.17335

Excitonic interactions and mechanism for ultrafast interlayer photoexcited response in van der Waals heterostructures

Chen Hu·Mit H. Naik·Yang-Hao Chan·Steven G. Louie
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Abstract

Optical dynamics in van der Waals heterobilayers is of fundamental scientific and practical interest. Based on a time-dependent adiabatic GW approach, we discover a new many-electron (excitonic) channel for converting photoexcited intralayer to interlayer excitations and the associated ultrafast optical responses in heterobilayers, which is conceptually different from the conventional single-particle picture. We find strong electron-hole interactions drive the dynamics and enhance the pump-probe optical responses by an order of magnitude with a rise time of ~300 fs in MoSe$_2$/WSe$_2$ heterobilayers, in agreement with experiment.

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Chen Hu, Mit H. Naik, Yang-Hao Chan, Steven G. Louie. 2023-05-27. Excitonic interactions and mechanism for ultrafast interlayer photoexcited response in van der Waals heterostructures. https://arxiv.org/abs/2305.17335

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