Long-lived period-doubled edge modes of interacting and disorder-free Floquet spin chains

Journal Article · 21 February 2022 · Communications Physics

DOI: https://doi.org/10.1038/s42005-022-00818-1 · OSTI ID:1846813

Yates, Daniel J. ^[1]; Abanov, Alexander G. ^[2]; Mitra, Aditi  ^[3]

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1. New York Univ. (NYU), NY (United States); NYU
2. Simons Center for Geometry and Physics, Stony Brook, NY (United States); Stony Brook Univ., NY (United States)
3. New York Univ. (NYU), NY (United States)

Floquet spin chains have been a venue for understanding topological states of matter that are qualitatively different from their static counterparts by, for example, hosting π edge modes that show stable period-doubled dynamics. However the stability of these edge modes to interactions has traditionally required the system to be many-body localized in order to suppress heating. In contrast, here we show that even in the absence of disorder, and in the presence of bulk heating, π edge modes are long lived. Their lifetime is extracted from exact diagonalization and is found to be non-perturbative in the interaction strength. A tunneling estimate for the lifetime is obtained by mapping the stroboscopic time-evolution to dynamics of a single particle in Krylov subspace. In this subspace, the π edge mode manifests as the quasi-stable edge mode of an inhomogeneous Su-Schrieffer-Heeger model whose dimerization vanishes in the bulk of the Krylov chain.

• Research Organization: New York Univ. (NYU), NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0010821
• OSTI ID: 1846813
• Journal Information: Communications Physics, Journal Name: Communications Physics Journal Issue: 1 Vol. 5; ISSN 2399-3650
• Publisher: Springer NatureCopyright Statement
• Country of Publication: United States
• Language: English