Spin nonclassicality and quantum phase transition in the XY spin model

Abstract

We study the behaviors of spin nonclassicality in critical systems of spin chains, with the spin nonclassicality measured by an informational quantifier based on the Wigner-Yanase skew information. For the XY spin chain with three-spin interaction, we evaluate both the single-spin and the nearest neighbour two-spin nonclassicalities, as well as their first-order derivatives. We demonstrate the effectiveness of these quantities of spin nonclassicality in revealing the critical points for quantum phase transition. The merits of the present approach to detecting quantum phase transition by spin nonclassicality lie in its easy computation, informational content and metrological significance.