Ground-state magnetic properties of the spin-32 transverse Ising model

The ground-state phase diagrams and the magnetization curves of the spin-32 transverse Ising model with longitudinal crystal field D are studied within the framework of mean-field theory (MFT) and effective-field theory (EFT), respectively. A simple calculation method of the internal energy is presented within the framework of EFT. In the ground-state phase diagram given by using EFT, the second-order phase transition line is divided into two segments by the first-order phase transition line: one starts from a critical end point and extends to D→-∞; the other one starts from a tricritical point and extends to D→+∞, while it does not occur in MFT. Some interesting phenomena of the first-order phase transition from one ordered phase to another one ordered have been found.