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This content will become publicly available on December 1, 2023

Title: Topological current divider in a Chern insulator junction
Abstract A Chern insulator is a two-dimensional material that hosts chiral edge states produced by the combination of topology with time reversal symmetry breaking. Such edge states are perfect one-dimensional conductors, which may exist not only on sample edges, but on any boundary between two materials with distinct topological invariants (or Chern numbers). Engineering of such interfaces is highly desirable due to emerging opportunities of using topological edge states for energy-efficient information transmission. Here, we report a chiral edge-current divider based on Chern insulator junctions formed within the layered topological magnet MnBi 2 Te 4 . We find that in a device containing a boundary between regions of different thickness, topological domains with different Chern numbers can coexist. At the domain boundary, a Chern insulator junction forms, where we identify a chiral edge mode along the junction interface. We use this to construct topological circuits in which the chiral edge current can be split, rerouted, or switched off by controlling the Chern numbers of the individual domains. Our results demonstrate MnBi 2 Te 4 as an emerging platform for topological circuits design.
Authors:
; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
1719797
Publication Date:
NSF-PAR ID:
10379378
Journal Name:
Nature Communications
Volume:
13
Issue:
1
ISSN:
2041-1723
Sponsoring Org:
National Science Foundation
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