Ground state and magnetic phase transitions of the spin Lieb nanolattice: Monte Carlo simulations

We study the ground state and magnetic properties of the spin Lieb nanolattice with three lattice sites with spins (S = 2, sigma = 1/2, q = 3/2) using Monte Carlo simulations. The ground state phase diagrams of the Lieb nanolattice have been studied. The phase diagrams show some key features: coexistence between regions, points where six, eight and ten states can coexist. The total and partial magnetization of each sublattice is given and the corresponding magnetic susceptibility is also found. The variation of total magnetization with the exchange interaction R-sq and R-sigma q of the Lieb nanolattice with three lattice sites with spins (S, sigma, g) has been studied. Moreover, the total magnetization versus the fields Delta/J(S sigma) of the Lieb nanolattice with three lattice sites with spins (S, sigma, q) are established for several values of R-sigma q and R-sq. Magnetic hysteresis cycles of the Lieb nanolattice with three lattice sites with spins (S, sigma, q) are found for several values of R-sq and temperature. We show that the superparamagnetism behaviour appears for a weak coupling value between S and q thus around the transition temperature. (C) 2017 Elsevier B.V. All rights reserved.