The Studies Of Magnetic Properties In Mixed Ferrimagnetic Spin System

In this thesis, we perform Monte Carlo simulations to study the magnetic properties of a mixed spin-1 and spin-3/2 ferrimagnetic spin system with single-ion anisotropy. The main contents of this paper are arranged as follows:1. The essential conception, sort and physical characters ofnanostructured magnetic materials are introduced in brief. Following, we mostly present the basal theory and the Monte Carlo method which are involved in this paper.2. Base on the Monte Carlo simulation, we investigate the magnetic properties of a mixed spin-1 and spin-3/2 ferrimagnetic systems on a one-dimensional spin chain. It is found: (1) The magnetization plateaus under the external field at the ground state exist in the well-regulated systems; (2) A phase diagram of the mixed spin-1 and spin-3/2 ferrimagnetic systems is also observed, the magnetic plateaus and the phase diagrams of the systems have been explained well with the analysis of the energy and the spin configuration of the system; (3) Strong fluctuations may appear in this ferromagnetic system, and the step-like even disappears when the spin-1 and spin-3/2 in random array.3, We also perform the Monte Carlo simulation to study the magnetic properties of two-dimensional mixed ferrimagnetic spin system, The simulated results indicate that magnetization plateaus will occurred at the ground state, and the size influence on the mixed system evidently. Moreover, the magnetic plateaus and the phase diagrams of the systems are also explained well with the analysis of the energy and the spin configuration of the system.