Phase diagrams of the transverse Ising antiferromagnet in the presence of the longitudinal magnetic field

AbstractIn this paper we study the critical behavior of the two-dimensional antiferromagnetic Ising model in both uniform longitudinal (H) and transverse (Ω) magnetic fields. Using the effective-field theory (EFT) with correlation in single site clusters we calculate the phase diagrams in the H−T and Ω−T planes for the square lattice. We have only found second order phase transitions for all values of fields and reentrant behavior was not observed