THE PHENOMENON OF MAGNETIC REENTRANCY IN THE ISING MODEL ON A DECORATED SQUARE LATTICE

In this work, based on the exact solution of the Ising model on a decorated square lattice with an arbitrary number of decorating spins, the fundamental possibility of describing the phenomenon of magnetic reentrancy is revealed. It is established that magnetic reentrancy arises in the case of competition between exchange interactions in the considered spin systems. It has been found that in the system under study, only one, three, or five magnetic phase transitions are possible, which is confirmed by a complex magnetic phase diagram. A number of key scenarios for the formation of magnetic reentrancy are presented, illustrating the influence of model parameters on the magnetic behaviour of the system.