Fidelity approach to the disordered quantum XY model.
We study the random XY spin chain in a transverse field by analyzing the susceptibility of the ground state fidelity, numerically evaluated through a standard mapping of the model onto quasifree fermions. It is found that the fidelity susceptibility and its scaling properties provide useful information about the phase diagram. In particular it is possible to determine the Ising critical line and the Griffiths phase regions, in agreement with previous analytical and numerical results.
Garnerone
Silvano
S
Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, USA. garneron@usc.edu
Jacobson
N Tobias
NT
Haas
Stephan
S
Zanardi
Paolo
P