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arXiv · 2409.17633

Direct measurement of terahertz conductivity in a gated monolayer semiconductor

Su-Di Chen·Qixin Feng·Wenyu Zhao·Ruishi Qi·Zuocheng Zhang·Dishan Abeysinghe·Can Uzundal·Jingxu Xie·Takashi Taniguchi·Kenji Watanabe·Feng Wang
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Abstract

Two-dimensional semiconductors and their moir\'e superlattices have emerged as important platforms for investigating correlated electrons. However, many key properties of these systems, such as the frequency-dependent conductivity, remain experimentally inaccessible because of the mesoscopic sample size. Here we report a technique to directly measure the complex conductivity of electrostatically gated two-dimensional semiconductors in the terahertz frequency range. Applying this technique to a WSe2 monolayer encapsulated in hBN, we observe clear Drude-like response between 0.1 and 1 THz, in a density range challenging to access even in DC transport. Our work opens a new avenue for studying tunable van der Waals heterostructures using terahertz spectroscopy.

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Su-Di Chen, Qixin Feng, Wenyu Zhao, Ruishi Qi, Zuocheng Zhang, Dishan Abeysinghe, Can Uzundal, Jingxu Xie, Takashi Taniguchi, Kenji Watanabe, Feng Wang. 2024-09-26. Direct measurement of terahertz conductivity in a gated monolayer semiconductor. https://doi.org/10.1021/acs.nanolett.5c01605

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