1204.5769 (Wen-ge Wang et al.)

Scaling behavior in quantum phase transitions    [PDF]

Wen-ge Wang, Pinquan Qin, Giuliano Benenti, Giulio Casati

We show that for quantum phase transitions with a single bosonic zero mode at the critical point, like the Dicke model, metric quantities such as fidelity, that is, the overlap between two ground states corresponding to two values $\lambda_1$ and $\lambda_2$ of the controlling parameter $\lambda$, only depend on the ratio $\eta=(\lambda_1-\lambda_c)/(\lambda_2-\lambda_c)$, where $\lambda=\lambda_c$ at the critical point. Such scaling property is valid also for time-dependent quantities such as the Loschmidt echo, provided time is measured in unit of the inverse frequency of the critical mode.

View original: http://arxiv.org/abs/1204.5769