Phase diagrams of Ising films with competing interactions

Phase diagram of the Ising square lattice with competing interactions

We restudy the phase diagram of the 2D-Ising model with competing interactions J1 on nearest neighbour and J2 on next-nearest neighbour bonds via Monte-Carlo simulations. We present the finite temperature phase diagram and introduce computational methods which allow us to calculate transition temperatures close to the critical point at J2 = 0.5J1. Further on we investigate the character of the ...

Phase diagrams in the Blume-Emery-Griffiths Ising thin films

We study the spin-1 Ising model with bilinear and biquadratic exchange interactions and single-ion crystal field. In addition to the four usual phases: disordered DIS, ferromagnetic FER, antiquadrupolar AQU and ferrimagnetic FRI, we found three new phases in the case of a thin magnetic film, namely: the sublattice A non magnetic phase NMA, the sublattice B non magnetic phase NMB and the global ...

Two-dimensional ising model with competing interactions : floating phase, walls and dislocations

Slow coarsening in an Ising chain with competing interactions

We investigate the zero-temperature coarsening dynamics of a chain of Ising spins with a nearest-neighbour ferromagnetic and an nth-neighbour antiferromagnetic interactions. For sufficiently large antiferromagnetic interaction, the ground state consists of n consecutive up spins followed by n down spins, etc. We show that the asymptotic coarsening into this ground state can be described in term...

Ordering in Two-Dimensional Ising Models with Competing Interactions

We study the 2D Ising Model on a square lattice with additional non-equal diagonal next-nearest neighbor interactions. The cases of classical and quantum (transverse) models are considered. Possible phases and their locations in the space of three Ising couplings are analyzed. In particular, incommensurate phases, occurring only at non-equal diagonal couplings, are predicted. In a particular re...