Fundamental modes in waveguide pipe twisted by saturated double-well potential  

作　　者：Gui-Hua Chen Hong-Cheng Wang Zhao-Pin Chen Yan Liu 

机构地区：[1]Department of Electronic Engineering, Dongguan University of Technology, Dongguan 523808, China [2]Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv IL-69978, Israel [3]Department of Applied Physics, South China Agricultural University, Guangzhou 510642, China

出　　处：《Frontiers of physics》2017年第1期107-116,共10页物理学前沿（英文版）

基　　金：Acknowledgements G. Chen appreciates the useful discussions with Yongyao Li （SCAU Univ.）. This work was supported by the National Natural Science Foundation of China （Grant No. 61308019）, Guangdong Natural Science Foundation （Grant No. 2015A030313650）, and the Foundation for Distin- guished Young Talents in Higher Education of Guangdong （Grant No. Yq2013157）.

摘　　要：We study fundamental modes trapped in a rotating ring with a saturated nonlinear double-well potential. This model, which is based on the nonlinear Schrodinger equation, can be constructed in a twisted waveguide pipe in terms of light propagation, or in a Bose-Einstein condensate （BEC） loaded into a toroidal trap under a combination of a rotating π-out-of-phase linear potential and nonlinear pseudopotential induced by means of a rotating optical field and the Feshbach resonance. Three types of fundamental modes are identified in this model, one symmetric and the other two asymmetric. The shape and stability of the modes and the transitions between different modes are investigated in the first rotational Brillouin zone. A similar model used a Kerr medium to build its nonlinear potential, but we replace it with a saturated nonlinear medium. The model exhibits not only symmetry breaking, but also symmetry recovery. A specific type of unstable asymmetric mode is also found, and the evolution of the unstable asymmetric mode features Josephson oscillation between two linear wells. By considering the model as a configuration of a BEC system, the ground state mode is identified among these three types, which characterize a specific distribution of the BEC atoms around the trap.We study fundamental modes trapped in a rotating ring with a saturated nonlinear double-well potential. This model, which is based on the nonlinear Schrodinger equation, can be constructed in a twisted waveguide pipe in terms of light propagation, or in a Bose-Einstein condensate （BEC） loaded into a toroidal trap under a combination of a rotating π-out-of-phase linear potential and nonlinear pseudopotential induced by means of a rotating optical field and the Feshbach resonance. Three types of fundamental modes are identified in this model, one symmetric and the other two asymmetric. The shape and stability of the modes and the transitions between different modes are investigated in the first rotational Brillouin zone. A similar model used a Kerr medium to build its nonlinear potential, but we replace it with a saturated nonlinear medium. The model exhibits not only symmetry breaking, but also symmetry recovery. A specific type of unstable asymmetric mode is also found, and the evolution of the unstable asymmetric mode features Josephson oscillation between two linear wells. By considering the model as a configuration of a BEC system, the ground state mode is identified among these three types, which characterize a specific distribution of the BEC atoms around the trap.

关 键 词：Twisted double-well waveguide saturated nonlinear potential symmetry breaking symmetry recovery 

分 类 号：O437[机械工程—光学工程] TN253.01[理学—光学]