Dynamical Evolution of an Effective Two-Level System with $\mathcal{PT}$ Symmetry
Lei Du1, Zhihao Xu1,2,3, Chuanhao Yin4, Liping Guo1,2,3**
1Institute of Theoretical Physics, Shanxi University, Taiyuan 030006 2Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006 3State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 4Institute of Physics, Chinese Academy of Sciences, Beijing 100190
Abstract：We investigate the dynamics of parity- and time-reversal ($\mathcal{PT}$) symmetric two-energy-level atoms in the presence of two optical and one radio-frequency fields. The strength and relative phase of fields can drive the system from the unbroken to the broken $\mathcal{PT}$ symmetric regions. Compared with the Hermitian model, Rabi-type oscillation is still observed, and the oscillation characteristics are also adjusted by the strength and relative phase in the region of the unbroken $\mathcal{PT}$ symmetry. At the exception point, the oscillation breaks down. To better understand the underlying properties we study the effective Bloch dynamics and find that the emergence of the $z$ components of the fixed points is the feature of the $\mathcal{PT}$ symmetry breaking and the projections in the $x$–$y$ plane can be controlled with high flexibility compared with the standard two-level system with the $\mathcal{PT}$ symmetry. It helps to study the dynamic behavior of the complex $\mathcal{PT}$ symmetric model.
. [J]. 中国物理快报, 2018, 35(5): 50301-.
Lei Du, Zhihao Xu, Chuanhao Yin, Liping Guo. Dynamical Evolution of an Effective Two-Level System with $\mathcal{PT}$ Symmetry. Chin. Phys. Lett., 2018, 35(5): 50301-.
2018, Vol. 35 
