Charge-Density-Wave Proximity Effects in Graphene

Boram Kim; Jeehoon Park; Jinshu Li; Hongsik Lim; Gyuho Myeong; Wongil Shin; Seungho Kim; Taehyeok Jin; Qi Zhang; Kyunghwan Sung; Kenji Watanabe; Takashi Taniguchi; Euyheon Hwang; Sungjae Cho

arXiv · 2201.04844

Charge-Density-Wave Proximity Effects in Graphene

Boram Kim·Jeehoon Park·Jinshu Li·Hongsik Lim·Gyuho Myeong·Wongil Shin·Seungho Kim·Taehyeok Jin·Qi Zhang·Kyunghwan Sung·Kenji Watanabe·Takashi Taniguchi·Euyheon Hwang·Sungjae Cho

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Abstract

Certain layered transition metal dichalcogenides (TMDCs), such as 1T-TaS2, show a rich collection of charge density wave (CDW) phases at different temperatures, and their atomic structures and electron conductions have been widely studied. However, the properties of CDW systems that are integrated with other electronic materials have not yet been investigated. Here, we incorporate the CDW properties of TMDCs into the electronic transport of graphene for the first time. During CDW phase transitions, anomalous transport behaviors that are closely related to the formation of correlated disorder in TMDCs were observed in the graphene sample used in this study. In particular, the commensurate CDW phase forms a periodic charge distribution with potential fluctuations, and thus constitutes correlated charged impurities, which decreases resistivity and enhances carrier mobility in graphene. The CDW-graphene heterostructure system demonstrated here paves the way to controlling the temperature-dependent carrier mobility and resistivity of graphene and to developing novel functional electronic devices such as graphene-based sensors and memory devices.

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Boram Kim, Jeehoon Park, Jinshu Li, Hongsik Lim, Gyuho Myeong, Wongil Shin, Seungho Kim, Taehyeok Jin, Qi Zhang, Kyunghwan Sung, Kenji Watanabe, Takashi Taniguchi, Euyheon Hwang, Sungjae Cho. 2022-01-13. Charge-Density-Wave Proximity Effects in Graphene. https://arxiv.org/abs/2201.04844

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