期刊
NATURE PHYSICS
卷 18, 期 2, 页码 196-+出版社
NATURE PORTFOLIO
DOI: 10.1038/s41567-021-01438-2
关键词
-
资金
- Programmable Quantum Materials, an Energy Frontier Research Center - US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES) [DE-SC0019443]
- Air Force Office of Scientific Research [FA9550-16-1-0601]
- European Union Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant [844271]
- European Research Council [ERC-2015-AdG-694097]
- Grupos Consolidados [IT1249-19]
- Flatiron Institute, a division of the Simons Foundation
- Deutsche Forschungsgemeinschaft (DFG) [EXC 2004/1-390534769, EXC 2056-390715994, RTG 1995, GRK 2247]
- Max Planck Institute-New York City Center for Non-Equilibrium Quantum Phenomena
- NSF MRSEC programme [DMR-1420634]
- RWTH Aachen University [rwth0496, rwth0589]
- National Science Foundation [DMR-2002850]
- DOE-BES [DE-SC0020045]
- Elemental Strategy Initiative conducted by the MEXT, Japan [JPMXP0112101001]
- JSPS KAKENHI [JP20H00354]
- CREST [JPMJCR15F3]
- Marie Curie Actions (MSCA) [844271] Funding Source: Marie Curie Actions (MSCA)
- U.S. Department of Energy (DOE) [DE-SC0020045] Funding Source: U.S. Department of Energy (DOE)
A study on twisted double bilayer graphene reveals the presence of three-fold rotational symmetry breaking, indicative of an interaction-driven electronic nematic phase that emerges from the normal metal state and is related to the scale of the moire lattice.
Graphene moire superlattices display electronic flat bands. At integer fillings of these flat bands, energy gaps due to strong electron-electron interactions are generally observed. However, the presence of other correlation-driven phases in twisted graphitic systems at non-integer fillings is unclear. Here, we report the existence of three-fold rotational (C-3) symmetry breaking in twisted double bilayer graphene. Using spectroscopic imaging over large and uniform areas to characterize the direction and degree of C-3 symmetry breaking, we find it to be prominent only at energies corresponding to the flat bands and nearly absent in the remote bands. We demonstrate that the magnitude of the rotational symmetry breaking does not depend on the degree of the heterostrain or the displacement field, being instead a manifestation of an interaction-driven electronic nematic phase. We show that the nematic phase is a primary order that arises from the normal metal state over a wide range of doping away from charge neutrality. Our modelling suggests that the nematic instability is not associated with the local scale of the graphene lattice, but is an emergent phenomenon at the scale of the moire lattice. Observations of an electronic nematic phase in twisted double bilayer graphene expand the number of moire materials where this interaction-driven state exists.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据