Floquet gap-dependent topological classifications from color-decorated frequency lattices with space-time symmetries

被引：1

作者：

Na, Ilyoun ^{[1
,2
,3
]}

Kemp, Jack ^{[4
]}

Griffin, Sinead M. ^{[2
,3
]}

Slager, Robert-Jan ^{[5
]}

Peng, Yang ^{[6
,7
]}

机构：

[1] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA

[2] Lawrence Berkeley Natl Lab, Mat Sci Div, Berkeley, CA 94720 USA

[3] Lawrence Berkeley Natl Lab, Mol Foundry, Berkeley, CA 94720 USA

[4] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA

[5] Cavendish Lab, Dept Phys, TCM Grp, JJ Thomson Ave, Cambridge CB3 0HE, England

[6] Calif State Univ Northridge, Dept Phys & Astron, Northridge, CA 91330 USA

[7] CALTECH, Dept Phys, Pasadena, CA 91125 USA

来源：

PHYSICAL REVIEW B | 2023年 / 108卷 / 18期

基金：

美国国家科学基金会; 英国工程与自然科学研究理事会;

关键词：

All Open Access; Green;

D O I：

10.1103/PhysRevB.108.L180302

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We find a class of Floquet topological phases exhibiting gap-dependent topological classifications in quantum systems with a dynamical space-time symmetry and an antisymmetry. This is in contrast to all existing Floquet topological phases protected by static symmetries, where the topological classification across all quasienergy gaps is characterized by the same Abelian group. We demonstrate this gap-dependent classification phenomenon using the frequency-domain formulation of the time-dependent Hamiltonian. Moreover, we provide an interpretation of the resulting Floquet topological phases using a frequency lattice with a decoration represented by color degrees of freedom on the lattice vertices. These colors correspond to the coefficient N of the group extension of the system symmetry group G along the frequency lattice, given by N = Z x H1[A, M]. The distinct topological classifications that arise at different energy gaps in its quasienergy spectrum are described by the torsion product of the cohomology group H2[G, N] classifying the group extension.

引用

页数：6