相关论文: Critical behavior of magnetic thin films as a func…
Using Monte Carlo techniques and a star-triangle transformation, Ising models with random, 'strong' and 'weak', nearest-neighbour ferromagnetic couplings on a square lattice with a (1,1) surface are studied near the phase transition. Both…
A one-dimensional equation describing the distribution of the effective vector potential $\bar A(y)$ across a film width, which holds for thin ($d<\lambda$) and thick ($d>\lambda$) films alike, is derived based on the analysis of a 2D…
Taking the two-dimensional Ising model for example, short-time behavior of critical dynamics with a conserved order parameter is investigated by Monte Carlo simulations. Scaling behavior is observed, but the dynamic exponent $z$ is updating…
Ising models with nearest-neighbor ferromagnetic random couplings on a square lattice with a (1,1) surface are studied, using Monte Carlo techniques and star-tiangle transformation method. In particular, the critical exponent of the surface…
We review the value of the critical exponents $\nu^{-1}$, $\beta/\nu$, and $\gamma/\nu$ of ferromagnetic Ising model on fractal lattices of Hausdorff dimension between one and three. They are obtained by Monte Carlo simulation with the help…
Using Monte Carlo techniques, the critical behaviour at edges and corners of the three-dimensional Ising model is studied. In particular, the critical exponent $\beta_2$ of the local magnetization at edges formed by two intersecting free…
We present iterative Monte Carlo algorithm for which the temperature variable is attracted by a critical point. The algorithm combines techniques of single histogram reweighting and linear filtering. The 2d Ising model of ferromagnet is…
Imaging the magnetic configuration of thin-films has been a long-standing area of research. Since a few years, the emergence of two-dimensional ferromagnetic materials calls for innovation in the field of magnetic imaging. As the magnetic…
A large positive magnetoresistivity (up to tens of percents) is observed in both underdoped and overdoped superconducting La2-xSrxCuO4 epitaxial thin films at temperatures far above the superconducting critical temperature Tc. For the…
The expression of temperature distribution along a film thickness is derived and distribution of temperature in the film as the substrate is heated is shown. The variation of film resistance with different substrate temperature is…
Experiments on disordered superconducting thin films have revealed a magnetoresistance peak of several orders of magnitude. Starting from the disordered negative-U Hubbard model, we employ an ab initio approach that includes thermal…
The critical behaviour of thin films containing quenched random impurities and inhomogeneities is investigated by the renormalization-group method. The finite-size crossover in impure films has been considered on the basis of the…
We study the behavior of the two-dimensional Ising model in a finite box at temperatures that are below, but very close to, the critical temperature. In a regime where the temperature approaches the critical point and, simultaneously, the…
Upper critical fields of four MgB2 thin films were measured up to 28 Tesla at Grenoble High Magnetic Field Laboratory. The films were grown by Pulsed Laser Deposition and showed critical temperatures ranging between 29.5 and 38.8 K and…
We study the scaling of the magnetic susceptibility in the square Ising model based upon the delta-expansion in the high temperature phase. The susceptibility chi is expressed in terms of the mass M and expanded in powers of 1/M. The…
Below the Curie temperature T_c of a Heusler-alloy film, consisting of densely packed, but exchange-decoupled nanograins, the spontaneous magnetization M_s(T) and static in-plane susceptibility \chi_{||}(T) increase very slowly signalizing…
Magnetic and magnetotransport properties of oriented polycrystalline Pr0.58Ca0.42MnO3 thin films prepared in flowing oxygen and air ambient has been investigated. The magnetic ground state of both the films is a frozen cluster glass. In the…
The short-time critical dynamics of propagation of damage in the Ising ferromagnet in two dimensions is studied by means of Monte Carlo simulations. Starting with equilibrium configurations at $T= \infty$ and magnetization $M=0$, an initial…
This article gives a brief overview on recent advances in experiments of critical exponents in three groups of magnetic materials. Revisiting experimental data verifies that a universality class with the critical exponents beta = 3/8, gamma…
We present results of a Monte Carlo study for the ferromagnetic Ising model with long range interactions in two dimensions. This model has been simulated for a large range of interaction parameter $\sigma$ and for large sizes. We observe…