Magnetocaloric Effect and Magnetization Plateaus in TbB₄: The Monte Carlo Simulation

In this work, we have investigated the magnetocaloric effect and the magnetization plateaus of TbB4 in a frustrated Ising model. The results exhibit that the transition point shifts towards a higher magnetic field as the third nearest -neighbor couplings J(3) increases, and the transition between 1/3 plateau and 1/2 plateau of the system can be achieved by regulating J(3). Another interesting finding is that as the magnetic field increases, there are three local maxima in both magnetic entropy change Delta S and adiabatic temperature change Delta T, and when the system undergoes the transition between ferrimagnetic state and ferromagnetic state, the maximum values appear near the transition point. The results are explained qualitatively by the energy competitions. These findings may be helpful in the design of magnetic refrigeration experiments.