TY - JOUR

T1 - Edge states at an intersection of edges of a topological material

AU - Hashimoto, Koji

AU - Wu, Xi

AU - Kimura, Taro

N1 - Funding Information:
We would like to thank valuable discussions with H. Fukaya, T. Fukui, Y. Hatsugai, N. Kawakami, T. Onogi, and Y. Tanaka. The work of K.H. was supported in part by JSPS KAKENHI Grants No. JP15H03658 and No. JP15K13483. The work of T.K. was supported in part by Keio Gijuku Academic Development Funds, JSPS Grant-in-Aid for Scientific Research (No. JP17K18090), the MEXT-Supported Program for the Strategic Research Foundation at Private Universities Topological Science (No. S1511006), and JSPS Grant-in-Aid for Scientific Research on Innovative Areas Topological Materials Science (No. JP15H05855).
Publisher Copyright:
© 2017 American Physical Society.

PY - 2017/4/25

Y1 - 2017/4/25

N2 - We study an exotic state which is localized only at an intersection of edges of a topological material. This "edge-of-edge" state is shown to exist generically. We construct explicitly generic edge-of-edge states in five-dimensional Weyl semimetals and their dimensional reductions, such as four-dimensional topological insulators of class A and three-dimensional chiral topological insulators of class AIII. The existence of the edge-of-edge state is due to a topological charge of the edge states. The notion of the Berry connection is generalized to include the space of all possible boundary conditions, where Chern-Simons forms are shown to be nontrivial.

AB - We study an exotic state which is localized only at an intersection of edges of a topological material. This "edge-of-edge" state is shown to exist generically. We construct explicitly generic edge-of-edge states in five-dimensional Weyl semimetals and their dimensional reductions, such as four-dimensional topological insulators of class A and three-dimensional chiral topological insulators of class AIII. The existence of the edge-of-edge state is due to a topological charge of the edge states. The notion of the Berry connection is generalized to include the space of all possible boundary conditions, where Chern-Simons forms are shown to be nontrivial.

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U2 - 10.1103/PhysRevB.95.165443

DO - 10.1103/PhysRevB.95.165443

M3 - Article

AN - SCOPUS:85018297487

VL - 95

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 2469-9950

IS - 16

M1 - 165443

ER -