Floquet generation of hybrid-order topology and ℤ2-like bipolar localization
- 1Indian Institute of Technology Guwahati
- 2Bilkent University
Abstract
Periodic driving offers a powerful tool to engineer topological phases and even induce phase transitions that are inaccessible in static settings. In this work, we demonstrate that a suitable driving protocol applied to the Benalcazar-Bernevig-Hughes model, a canonical quadrupolar insulator with a π -flux-induced projective PT symmetry, gives rise to a topological phase in which the dispersive first-order edge states and localized higher-order corner modes are shown to coexist at distinct quasienergies. Further, extending the scenario to nonreciprocal-hopping-induced non-Hermiticity, we uncover a Z 2 -like skin effect characterized by a sharp transition from a unipolar to a bipolar eigenstate-localized phase. Remarkably, this phenomenon, which is established as a prerogative for spinful systems, emerges here purely from the interplay between the embedded gauge structure and Floquet-renormalized symmetry constraints, without invoking physical spin degrees of freedom. Further, the broken bulk-boundary correspondence in this driven non-Hermitian setting can be restored via computing the two-dimensional generalized Brillouin zone, which we construct through a symmetry-reduced mapping onto an effective one-dimensional problem. The resulting non-Bloch invariants faithfully capture both the higher-order topology and the unipolar to bipolar transition. These findings reveal periodic driving as a versatile and controllable handle for sculpting the interplay of higher-order topology, symmetry transmutation, and non-Hermitian skin physics in a single unified platform.
Versions
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BibTeX
@article{roy2026floquet,
title = {{Floquet generation of hybrid-order topology and $\mathbbZ_2$-like bipolar localization}},
author = {Koustav Roy and Latu Kalita and B. Tanatar and Saurabh Basu},
journal = {Physical Review Research},
year = {2026},
month = oct,
doi = {10.1103/rlrh-clk2},
url = {http://link.aps.org/doi/10.1103/rlrh-clk2},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Floquet generation of hybrid-order topology and ℤ_2-like bipolar localization
AU - Koustav Roy
AU - Latu Kalita
AU - B. Tanatar
AU - Saurabh Basu
PY - 2026
DA - 2026/10/26
JO - Physical Review Research
DO - 10.1103/rlrh-clk2
UR - http://link.aps.org/doi/10.1103/rlrh-clk2
AB - Periodic driving offers a powerful tool to engineer topological phases and even induce phase transitions that are inaccessible in static settings. In this work, we demonstrate that a suitable driving protocol applied to the Benalcazar-Bernevig-Hughes model, a canonical quadrupolar insulator with a π -flux-induced projective PT symmetry, gives rise to a topological phase in which the dispersive first-order edge states and localized higher-order corner modes are shown to coexist at distinct quasienergies. Further, extending the scenario to nonreciprocal-hopping-induced non-Hermiticity, we uncover a Z 2 -like skin effect characterized by a sharp transition from a unipolar to a bipolar eigenstate-localized phase. Remarkably, this phenomenon, which is established as a prerogative for spinful systems, emerges here purely from the interplay between the embedded gauge structure and Floquet-renormalized symmetry constraints, without invoking physical spin degrees of freedom. Further, the broken bulk-boundary correspondence in this driven non-Hermitian setting can be restored via computing the two-dimensional generalized Brillouin zone, which we construct through a symmetry-reduced mapping onto an effective one-dimensional problem. The resulting non-Bloch invariants faithfully capture both the higher-order topology and the unipolar to bipolar transition. These findings reveal periodic driving as a versatile and controllable handle for sculpting the interplay of higher-order topology, symmetry transmutation, and non-Hermitian skin physics in a single unified platform.
SN - 2643-1564
ER -