Topologically protected edge states in chiral-symmetric phononic time crystals
Phys. Rev. B 113, 205431 – Published 27 May, 2026
DOI: https://doi.org/10.1103/hwhz-ckvc
Abstract
It is well known that an interface created by two topologically distinct phononic space structures could host nontrivial edge states that are immune to defects. Here, we propose a new class of phononic time crystals presenting chiral symmetry, and demonstrate the temporal version of topological edge states that exhibit superior robust properties. Our proposed phononic time crystal is equivalent to a temporal version of the Su-Schrieffer-Heeger model, and the chiral symmetry of this type of phononic time crystals quantizes the winding number defined in the Bloch frequency band. Specifically, the random temporal disorders do not impact the eigenfrequencies of the chiral-symmetry-protected edge states, while instead enhancing the temporal localizations of acoustic waves. Our work paves the way towards topological temporal control of acoustic wave with unique robustness.
