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arXiv · 2303.13982

Designing nontrivial one-dimensional Floquet topological phases using a spin-1/2 double-kicked rotor

Abstract

A quantum kicked rotor model is one of the promising systems to realize various Floquet topological phases. We consider a double-kicked rotor model for a one-dimensional quasi-spin-1/2 Bose-Einstein condensate with spin-dependent and spin-independent kicks which are implementable for cold atomic experiments. We theoretically show that the model can realize all the Altland-Zirnbauer classes with nontrivial topology in one dimension. In the case of class CII, we show that a pair of winding numbers $(w_0,w_π)\in 2\mathbb{Z}\times 2\mathbb{Z}$ featuring the edge states at zero and $π$ quasienergy, respectively, takes various values depending on the strengths of the kicks. We also find that the winding numbers change to $\mathbb{Z}$ when we break the time-reversal and particle-hole symmetries by changing the phase of a kicking lattice. We numerically confirm that the winding numbers can be obtained by measuring the mean chiral displacement in the long-time limit in the present case with four internal degrees of freedom. We further propose two feasible methods to experimentally realize the spin-dependent and spin-independent kicks required for various topological phases.

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Yusuke Koyama, Kazuya Fujimoto, Shuta Nakajima, Yuki Kawaguchi. 2023-11-23. Designing nontrivial one-dimensional Floquet topological phases using a spin-1/2 double-kicked rotor. https://doi.org/10.1103/physrevresearch.5.043167

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