https://doi.org/10.1140/epjd/e2016-70240-4
Regular Article
Floquet modulation of 
symmetry in an atomic Bose-Josephson junction
1 School of Physics and Astronomy, Sun Yat-Sen University, Zhuhai 519082, P.R. China
2 Department of Physics, Jishou University, Jishou 416000, P.R. China
3 State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-Sen University, Guangzhou 510275, P.R. China
4 Department of Physics and Mathematics, Hunan Institute of Technology, Hengyang 421002, P.R. China
a
e-mail: lichaoh2@mail.sysu.edu.cn
Received: 5 April 2016
Published online: 20 July 2016
We study a periodically driven -symmetric Bose-Josephson junction and explore how the driving field affects the symmetry in such a non-Hermitian many-body quantum system. In the absence of interaction, by employing the high-frequency Floquet method, the condition of spontaneous -symmetry-breaking transition is analytically given. In the presence of interaction, it is found that even weak atom-atom interaction can shift the critical point of the -symmetry-breaking transition. Furthermore, we numerically obtain the -symmetric phase diagram, where the region of unbroken symmetry sensitively depends on the interaction strength and the driving parameter. Our results provide a promising way for manipulating -symmetric many-body quantum system by utilizing periodic driving fields.
Key words: Cold Matter and Quantum Gas
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2016
