Ground State Properties of One-Dimensional Quantum Chiral XY -model

Abstract

We investigate ground state properties of a one-dimensional quantum chiral XY -model in a magnetic field. Numerical calculations are carried out by using a method of density matrix renormalization group. We also analyze behaviors of perturbation series for the ground state energy. For a special case that the natural cantedness is π⁄2, a value of the critical magnetic field for saturation of magnetization is shown to be given exactly in terms of the smallest zero of the Bessel function J₀(x ). We obtain the ground state phase diagram.