Unique phase diagrams in a graphene-like transverse Ising nanoparticle

The phase diagrams and the magnetizations in a graphene-like two-dimensional nanoparticle described by the transverse Ising model are investigated by the use of the effective-field theory with correlations. We have found some characteristic behaviors especially for the system with a small transverse field and a small surface exchange interaction, such as the reentrant phenomena.

Amorphization in an Ising nanowire

The phase diagrams and magnetizations of an Ising nanowire with an amorphization are investigated by the use of the effective field theory with correlations. Some characteristic phenomena have been found in them. The reduced total magnetization falls below that of its corresponding crystalline ferromagnetic nanowire. The reentrant phenomena have been obtained, when the value of amorphization [Formula: see text] becomes larger than a critical value ([Formula: see text]).

The magnetic susceptibility on the transverse antiferromagnetic Ising model: Analysis of the reentrant behavior

We study the three-dimensional antiferromagnetic Ising model in both uniform longitudinal [Formula: see text] and transverse [Formula: see text] magnetic fields by using the effective-field theory (EFT) with finite cluster [Formula: see text] spin (EFT-1). We analyzed the behavior of the magnetic susceptibility to investigate the reentrant phenomena that we have seen in the same phase diagram previously obtained in other papers. Our results shows the presence of two divergences in the susceptibility that indicates the existence of a reentrant behavior.