摘要
Recent measurement on an LC resonator magnetically coupled to a superconducting qubit [Phys.Rev.Lett.105 (2010)237001] shows that the system operates in the ultra-strong coupling regime and crosses the limit of validity for the rotating-wave approximation of the Jaynes-Cummings model By using extended bosonic coherent states,we solve the Jaynes-Cummings model exactly without using the rotating-wave approximation.Our numerically exact results for the spectrum of the flux qubit coupled to the LC resonator are fully consistent with the experimental observations.The smallest Bloch-Siegert shift obtained is consistent with that observed in this experiment.In addition,the Bloch-Siegert shifts in arbitrary level transitions and for arbitrary coupling constants are predicted.
作者
CHEN Qing-Hu
LI Lei
LIU Tao
WANG Ke-Lin
陈庆虎;黎雷;刘涛;汪克林(Center for Statistical and Theoretical Condensed Matter Physics,Zhejiang Normal University,Jinhua 321004;Department of Physics,Zhejiang University,Hangzhou 310027;School of Science,Southwest University of Science and Technology,Mianyang 621010;Department of Modern Physics,University of Science and Technology of China,Hefei 230026)
基金
Supported by the National Natural Science Foundation of China under Grant No 11174254
the National Basic Research Program of China under Grant No 2009CB929104.
