arXiv subjects

Yanfang Xia

Publications and source records attributed to Yanfang Xia.

6 recordsLinked to original sources

arXiv2023

The Effect of Ionic Spin on Multiferroic of Orthorhombic Perovskite

To investigate the influence of ion spin on the coupling between ferromagnetism and ferroelectricity in type II multiferroic perovskite, we prepared the multiferroic perovskite Er0.9La0.1Cr0.8Fe0.2O3 (ELCFO) using the sol-gel method, and explored the macroscopic magnetic properties of ELCFO through Mössbauer spectrum and magnetic testing. The thermal magnetic curve was analyzed to examine the state and change of each ionic spin in the ELCFO system at different temperature ranges, and the role of ionic spin in the coupling between ferromagnetism and ferroelectricity was investigated. This study provides a theoretical basis for further research on multiferroic perovskites and has practical implications.

cond-mat.mtrl-sci↗

arXiv2022

Unraveling the nature of thermally induced spin reorientation in NdFe1-xCrxO3

Understanding spin control mechanisms is an important part of condensed matter physics and the theoretical basis for designing spintronic devices. In this letter, based on four-sublattices molecular field theory, we propose that the underlying NdFe1-xCrxO3 magnetic mechanism is driven by spin reorientation sensitive to temperature. The actual coupling angular momentum, angle between the Nd3+ and Cr3+/Fe3+ moments at the given temperature is realized via the Nd3+ magnetic moment projection onto the Cr3+/Fe3+ plane. As the temperature increases, the angle between the moment of Nd3+ and the moment of Cr3+/Fe3+ decreases monotonically. In this work, the magnetic mechanism of NdFe1-xCrxO3 (x=0.1, 0.9), the close relationship between A/B angle and temperature are presented, which laid a theoretical foundation for the design of new multifunctional magnetic materials.

cond-mat.mtrl-sci↗

arXiv2022

Special spin behavior of rare earth ions at the A site of polycrystalline ErFe1-xCrxO3 (x = 0.1, 0.9)

Thermally induced spin control is one of the main directions for future spin devices. In this study, we synthesized single-phase polycrystalline ErFe1-xCrxO3 and combined the magnetization curves and Mössbauer spectra to determine the macroscopic magnetism at room temperature. The magnetization of the system at various temperatures is well simulated by molecular field theory. And it is found that under the DM interaction, not only the B-site ions undergo a reorientation process, but the spins of the A-site ions also change at the same time. The effective spin is defined as the projection of Er3+ on the Fe3+/Cr3+ spin plane, and the whole reorientation process is obtained by fitting. This study will complement the actual process of ErFe1-xCrxO3 spin reorientation and will lay a theoretical foundation for the fabrication of future spin-controlled devices.

cond-mat.mtrl-sci↗

arXiv2022

Unraveling the spin reorientation process in rare earth perovskite PrFe0.1Cr0.9O3

Ultrafast spin control plays a pivotal role in condensed matter physics. In this study, we analyzed the macroscopic magnetization of the PrFe0.1Cr0.9O3 system by molecular field model fitting. And the whole process of system spin reorientation is accurately calculated in the fitting process. It is found that, unlike the rare-earth perovskites we have previously studied, PrFe0.1Cr0.9O3 exhibits spin-reversion properties during the reorientation process. This research will lay a theoretical foundation for precise spin control in the future.

cond-mat.mtrl-sci↗

arXiv2022

Unraveling Thermally Induced Spin reorientation of Strongly Disordered NdFe0.5Cr0.5O3 System

Sophisticated spin instruments require high-precision spin control. In this study, we accurately study the intrinsic magnetic properties of the strongly disordered system NdFe0.5Cr0.5O3 through molecular field models combined with ASD theory. The three constituent sub-magnetic phases of the system are separated, and their magnetization contributions are calculated separately. Fitting the angle of the A/B magnetic moment at a given temperature, the reorientation temperature point and temperature dependence of different magnetic phases are obtained. This research will provide a very good theoretical support for studying complex disordered systems and applying high-precision spin control and lay a foundation for the design of new functional materials.

physics.app-ph↗

arXiv2022

The distribution of B-site in the perovskite for a d5-d3 superexchange system studied with Molecular field theory and Monte Carlo simulation

The B-site disorder in the d5 - d3 system of perovskites has been analyzed with molecular field theory and Monte Carlo method. The model is applicable to RFe1-pCrpO3 at any p value. When the saturation magnetization MS and phase transition temperature TP are known, a model can be built to calculate the order or disorder distribution of lattice B-sites. We analyze the case that the Fe-Cr superexchange is antiferromagnetic and ferromagnetic coupling respectively. The simulation result shows that the theoretical calculation formula is suitable for the calculation of different B-site distribution. Through the simulation, we find that when the x and y are large, the system will appear obvious long-range order. The DM interaction has a certain influence on the saturation magnetization. Via calculation, we found that the distribution states of Fe and Cr do not always conform to the uniform distribution but rather exhibit an effect that reduces the Fe-Fe clustering. The establishment of this model offers an explanation for several previously contentious issues, e.g., what is the phase transition temperature range of double perovskite, and why the different phase transition temperatures with the same doping proportion. It provides theoretical guidance for the design of functional materials with an arbitrary phase transition temperature.

cond-mat.mtrl-sci↗