Local probe of bulk and edge states in a fractional Chern insulator.

Autor: Ji Z; Department of Physics, Stanford University, Stanford, CA, USA.; Department of Applied Physics, Stanford University, Stanford, CA, USA.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Park H; Department of Physics, University of Washington, Seattle, WA, USA., Barber ME; Department of Physics, Stanford University, Stanford, CA, USA.; Department of Applied Physics, Stanford University, Stanford, CA, USA.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Hu C; Department of Physics, University of Washington, Seattle, WA, USA., Watanabe K; Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba, Japan.; Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan., Taniguchi T; Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba, Japan.; Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan., Chu JH; Department of Physics, University of Washington, Seattle, WA, USA., Xu X; Department of Physics, University of Washington, Seattle, WA, USA. xuxd@uw.edu.; Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA. xuxd@uw.edu., Shen ZX; Department of Physics, Stanford University, Stanford, CA, USA. zxshen@stanford.edu.; Department of Applied Physics, Stanford University, Stanford, CA, USA. zxshen@stanford.edu.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. zxshen@stanford.edu.; Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA. zxshen@stanford.edu.
Jazyk: angličtina
Zdroj: Nature [Nature] 2024 Nov; Vol. 635 (8039), pp. 578-583. Date of Electronic Publication: 2024 Nov 20.
DOI: 10.1038/s41586-024-08092-7
Abstrakt: The fractional quantum Hall effect is a key example of topological quantum many-body phenomena, arising from the interplay between strong electron correlation, topological order and time-reversal symmetry breaking. Recently, a lattice analogue of the fractional quantum Hall effect at zero magnetic field has been observed, confirming the existence of a zero-field fractional Chern insulator (FCI). Despite this, the bulk-edge correspondence-a hallmark of a FCI featuring an insulating bulk with conductive edges-has not been directly observed. In fact, this correspondence has not been visualized in any system for fractional states owing to experimental challenges. Here we report the imaging of FCI edge states in twisted MoTe 2 (t-MoTe 2 ) using microwave impedance microscopy 1 . By tuning the carrier density, we observe the system evolving between metallic and FCI states, the latter of which exhibits insulating bulk and conductive edges, as expected from the bulk-boundary correspondence. Further analysis suggests the composite nature of the FCI edge states. We also observe the evolution of edge states across the topological phase transition as a function of interlayer electric field and reveal exciting prospects of neighbouring domains with different fractional orders. These findings pave the way for research into topologically protected one-dimensional interfaces between various anyonic states at zero magnetic field, such as gapped one-dimensional symmetry-protected phases with non-zero topological entanglement entropy, Halperin-Laughlin interfaces and the creation of non-abelian anyons.
Competing Interests: Competing interests: Z.-X.S. is a co-founder of PrimeNano Inc., which licensed the MIM technology from Stanford University. The other authors declare no competing interests.
(© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)
Databáze: MEDLINE
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