5. Conclusions

As it was shown, in some conditions (low temperature and/or strong exchange coupling) the classical CMC algorithm can produce incorrect results in the

probability. However, with lower probability, the cluster contains whole spins in the system (like in the Wolff algorithm) which is related to a random value of the α parameter. The modification of adding probability causes that the configurations necessary for modeling of real magnetization processes are available during MC iterations. In other words, if magnetization processes require separate behavior of the hard and soft phase, the simulation procedure will test such a possibility.

Theory, Application, and Implementation of Monte Carlo Method in Science and Technology

As a final test, the so-called reverse magnetization curves were simulated using the classical as well as modified adding probability. Initially, the system was saturated in the field direction (all spins are directed up), and then the field was switched off. During calculations the field was increased in the opposite direction. Magnetization, determined as average spin value in the field direction, as a function

add appeared in all studied examples. Note

of the external magnetic field for all examined cases is shown in Figure 6.

that for the one-bridge system (relatively low interactions between the hard and

Spin configurations depicting the reverse magnetization process for the seven-bridge system at kB T = 1e‒4 eV.

Red and blue colors indicate the soft and hard phase, respectively.

The difference between Padd and P<sup>0</sup>

Figure 7.

application of multiphase magnetic systems. The problem lies in the adding probability used in the cluster-building procedures. This problem can be overcome by the proposed modification of Padd accompanied by the specific Metropolis-like algorithm. The key point is to recognize a property that influences the system clusterization and, next, introduction of the local information entropy of this property into the adding probability.

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In summary, one can conclude that the method proposed for modeling of magnetic systems allows sampling spin configurations practically inaccessible by original Wolff clusterization procedure. An interesting future of our method is the acceleration of the energy minimization process.
