This paper reports the novel binder-free and self-supported electrodes of hierarchical nickel cobalt phosphide NiCoP films decorated with size-controlled Ag quantum dots by magnetron sputtering (Ag/NiCoP). Ag quantum dots with...

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Based on Monte Carlo simulation we study the coercivity of iron nanowire deposited in chemically widened anodic aluminum oxide films. The coercivity is found to depend on the diameter and aspect ratio of the nanowire, and it decreases with increasing nanowire diameter, which is consistent with the experimental result. Two kinds of discretization cells regular global-shaped and regular cubic-shaped are used as minimum element. The simulation result reveals that the regular global-shaped discretization cell allows for more accurate calculated result while comparing to the experimental result than the cubic-shaped discretization cell does. The simulated coercivity as a function of temperature with different diameters shows that the data can be described well by the T-c power-law, and the diameter dependence of the exponent c displays a maximum peak.

Based on Monte Carlo (MC) simulation, the magnetization behavior of mixed ferrimagnetic spin system with single-ion anisotropy under external field is investigated. It is assumed that the element of the mixed system is composed of spin-1 and spin-3/2 by turns. The simulated results indicate that there exist the magnetization curves at the ground state on the one-dimensional spin chain, two-dimensional spin system as well as three-dimensional spin system. It found that the size, anisotropy constant and spin configurations influence evidently the magnetic properties of the mixed system. Moreover, the magnetic plateaus and the phase diagrams of the systems can be well interpreted in terms of the simple calculation of energy.

Based on the Monte-Carlo simulation and fast Fourier transformation-micro-magnetism (FFTM) method, magnetic properties with different parameters for the 4×4 Magnetic Quantum Dot Arrays (QDA) were studied. The calculating processes show that the same calculated results can be obtained by both methods above. But the FFTM method can save much time in obtaining results, which suggest that the method be employed to study more complex systems. The calculated results indicate that there exists obvious difference in the magnetic hysteresis loops with different temperatures, which can be well explained by considering the relationship between the easy-magnetization axis and the organization anisotropy of the QDA system. Furthermore, saturation field (Hs) increases with the dipolar interaction increasing, which is attributed to the competition between dipolar energy (ED) and Zeeman energy (EZ). The calculated results can fit the experimental results very well. Besides, it is found that the dipolar interaction constant D has a great influence on magnetic properties.