Year: 2018
Type: article
Abstract: The double kicked rotor model is a physically realizable extension of the paradigmatic kicked rotor model in the study of quantum chaos. Even before the concept of Floquet topological phases became widely known, the discovery of the Hofstadter butterfly spectrum in the double kicked rotor model [J. Wang and J. Gong, Phys. Rev. A 77, 031405 (2008)] already suggested the importance of periodic driving to the generation of Floquet topological matter. In this work, we explore Floquet topological phases of a double kicked rotor with an extra spin-$1/2$ degree of freedom. The latter has been experimentally engineered in a quantum kicked rotor recently by loading $^{87}\mathrm{Rb}$ condensates into a periodically pulsed optical lattice. Theoretically, we found that under the on-resonance condition, the spin-$1/2$ double kicked rotor admits rich topological phases due to the interplay between its external and internal degrees of freedom. Each of these topological phases is characterized by a pair of winding numbers, whose combination predicts the number of topologically protected zero and $\ensuremath{\pi}$-quasienergy edge states in the system. Topological phases with arbitrarily large winding numbers can be easily found by tuning the kicking strength. We discuss an experimental proposal to realize this model in kicked $^{87}\mathrm{Rb}$ condensates, and suggest detecting its topological invariants by measuring the mean chiral displacement in momentum space.
Source: Physical Review A
Authors: Longwen Zhou, Jiangbin Gong
Institution: National University of Singapore
Language: Latvian
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Award: G3281651031
OpenAlex ID: W2794095512