Quench dynamics and ground state fidelity of the one-dimensional extended quantum compass model in a transverse field

R Jafari
2016 Journal of Physics A: Mathematical and Theoretical  
We study the ground state fidelity, fidelity susceptibility and quench dynamics of the extended quantum compass model in a transverse field. This model reveals a rich phase diagram which includes several critical surfaces depending on exchange couplings. We present a characterization of quantum phase transitions in terms of the ground state fidelity between two ground states obtained for two different values of external parameters. However, we derive scaling relations describing the singular
more » ... avior of fidelity susceptibility in the quantum critical surfaces. Moreover, we study the time evolution of the system after a critical quantum quench using the Loschmidt. We find that the revival times of Loschmidt echo are given by T_rev=N/2v_max, where N is the size of the system and v_max is the maximum of lower bound group velocity of quasi-particles. Although the fidelity susceptibility shows the same exponent in all critical surfaces, the structure of the revivals after critical quantum quenches displays two different regimes reflecting different equilibration dynamics.
doi:10.1088/1751-8113/49/18/185004 fatcat:mopdckjszbd2tkvpuokyjjq6yy