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Room-temperature ferroelectricity in MoTe₂ down to the atomic monolayer limit.

ABSTRACT: Ferroelectrics allow for a wide range of intriguing applications. However, maintaining ferroelectricity has been hampered by intrinsic depolarization effects. Here, by combining first-principles calculations and experimental studies, we report on the discovery of robust room-temperature out-of-plane ferroelectricity which is realized in the thinnest monolayer MoTe₂ with unexploited distorted 1T (d1T) phase. The origin of the ferroelectricity in d1T-MoTe₂ results from the spontaneous symmetry breaking due to the relative atomic displacements of Mo atoms and Te atoms. Furthermore, a large ON/OFF resistance ratio is achieved in ferroelectric devices composed of MoTe₂-based van der Waals heterostructure. Our work demonstrates that ferroelectricity can exist in two-dimensional layered material down to the atomic monolayer limit, which can result in new functionalities and achieve unexpected applications in atomic-scale electronic devices.

SUBMITTER: Yuan S

PROVIDER: S-EPMC6467908 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Room-temperature ferroelectricity in MoTe2 down to the atomic monolayer limit.

Yuan Shuoguo S Luo Xin X Chan Hung Lit HL Xiao Chengcheng C Dai Yawei Y Xie Maohai M Hao Jianhua J

Nature communications 20190416 1

Ferroelectrics allow for a wide range of intriguing applications. However, maintaining ferroelectricity has been hampered by intrinsic depolarization effects. Here, by combining first-principles calculations and experimental studies, we report on the discovery of robust room-temperature out-of-plane ferroelectricity which is realized in the thinnest monolayer MoTe2 with unexploited distorted 1T (d1T) phase. The origin of the ferroelectricity in d1T-MoTe2 results from the sp ...[more]

PMID: 30992431

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