Eur. Phys. J. D (2012) 66: 201
https://doi.org/10.1140/epjd/e2012-30197-x

Regular Article

Quantum Fisher information and chaos in the Dicke model

¹ Department of Physics, School of Science, Changchun University, Changchun 130022, P.R. China
² Zhejiang Institute of Modern Physics, Department of Physics, Zhejiang University, Hangzhou 310027, P.R. China
³ College of Physics, Jilin University, Changchun 130012, P.R. China

^a e-mail: ydbest@126.com

Received: 25 March 2012
Received in final form: 6 May 2012
Published online: 16 August 2012

Abstract

We used quantum Fisher information (QFI) to distinguish quantum chaotic and regular dynamics in Dicke model. The QFI, which reflects the geometric properties of a state in parameter space, characterizes the sensitivity of the state with respect to SU(2) rotations. With numerical computation we found that, quantum dynamics in chaotic and regular cases are well distinguished by QFI, especially in the long-time evolution, where the QFI in the chaotic situation is evidently larger than that in regular one, i.e. the chaotic nature enhances the sensitivity of the system, as expected usually. We also plotted the time-averaged QFI in phase space, and found a good quantum-classical correspondence.