Finite-Temperature Scaling of Magnetic Susceptibility in the XY Spin Chain
H. T. Quan
Abstract
We study the magnetic susceptibility of 1D quantum XY model, and show that when the temperature approaches zero, the magnetic susceptibility (MS) exhibits finite-temperature scaling behavior. This scaling behavior of MS in 1D quantum XY model, due to the quantum-classical map, can be regarded as a witness of macroscopic quantum entanglement, and can be experimentally tested. Furthermore, the universality in the critical properties of MS in quantum XY model is verified. Our study also reveals the close relation between MS and geometric phase in some quantum phase transition systems, which has been studied recently.