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Title: Corner states in a second-order mechanical topological insulator
Abstract Demonstration of topological boundary modes in elastic systems has attracted a great deal of attention over the past few years due to its unique protection characteristic. Recently, second-order topological insulators have been proposed in manipulating the topologically protected localized states emerging only at corners. Here, we numerically and experimentally study corner states in a two-dimensional phononic crystal, namely a continuous elastic plate with embedded bolts in a hexagonal pattern. We create interfacial corners by adjoining trivial and non-trivial topological configurations. Due to the rich interaction between the bolts and the continuous elastic plate, we find a variety of corner states of and devoid of topological origin. Strikingly, some of the corner states are not only highly-localized but also tunable. Taking advantage of this property, we experimentally demonstrate asymmetric corner localization in a Z-shaped domain wall. This finding could create interest in exploration of tunable corner states for the use of advanced control of wave localization.  more » « less
Award ID(s):
1741685
NSF-PAR ID:
10283189
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Communications Materials
Volume:
2
Issue:
1
ISSN:
2662-4443
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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