Thermodynamic and magnetic properties in two artificial frustrated lattices

Phase transition and monopole densities in a nearest neighbor two-dimensional spin ice model

“…We observe two main differences relative to the simulations of the long range dipolar interaction system presented in ref. [37,38] -first, in contrast with the long range results, the critical temperature shows a dependence with the lattice size, as we expect for a nearest neighbor interaction. So, T C decreases as the size of the lattice grows.…”

“…Within the results we have we can estimate the transition temperature in the range 7.7 ≤ T C k B /D ≤ 7.8. If we apply the effective dipolar coupling D ef f = 0.9633D, as discussed in section II, it points to a transition temperature of T C ≈ 7.46D/k B , to be compared with the results presented for the long range dipolar model, given by T C = 7.2D/k B [37] or T C = 7.13D/k B [38]. The four spins that are adjacent to a given site j are given by S x j , S y j , S x j−1 and S y j+L (fig 1(b)).…”

“…In the present work we will use an extension of the nn2DSI model to study the thermodynamics of the two dimensional square spin ice in the canonical ensemble and compare its results to those obtained by considering the long range character of the dipolar interaction, presented in references [37,38]. There, the authors used Monte Carlo simulations to develop a study of the thermodynamics of the model, including the interaction between all the pairs of spins on finite lattices, with periodic boundary conditions treated by the Ewald summation technique [39] or with open boundary conditions.…”

The Magnetic Properties of Closely Spaced Three‐Dimensional Nanomagnet Array

“…Start from an initial random magnetic state at very high temperature, and end with a final ground state when the temperature is decreased to 0.01 D with temperature interval of 0.01 D. Moreover, the hysteresis loop is simulated for two different space distances, that is, two different dipolar coupling parameters. To simulate the magnetization reversal behavior, as described in our previous work [14], the magnetic field is first applied and increased to a certain field where the system reaches the saturated state. After saturating the magnetization in the positive direction, the field is subsequently reduced to zero and increased to − in steps of 0.01 and then increased to the positive saturated field + , so that a full hysteresis loop is completed.…”

“…Experimentally, the nanomagnet array can be realized by conventional electron-beam lithography [6,7]. For one-dimensional (1D) or two-dimensional (2D) array of nanomagnets, the magnetic properties have been extensively investigated experimentally or theoretically in the past decades [8][9][10][11][12][13][14]. However, the three-dimensional (3D) nanomagnet array received a little attention until recently due to the difficulty of fabrication in experiment [15].…”