相关论文: Universality classes and crossover scaling of Bark…

We investigate dynamic hysteresis and Barkhausen noise in ferromagnetic materials with a huge number of parallel and rigid Bloch domain walls. Considering a disordered ferromagnetic system with strong in-plane uniaxial anisotropy and…

The magnetic domain wall motion driven by a magnetic field is studied in (Ga,Mn)As and (Ga,Mn)(As,P) films of different thicknesses. In the thermally activated creep regime, a kink in the velocity curves and a jump of the roughness exponent…

We explore the magnetic-field-driven motion of domain walls with different chiralities in thin ferromagnetic films made of Pt/Co/Pt, Au/Co/Pt, and Pt/Co/Au. From the analysis of domain wall dynamics, we extract parameters characterizing the…

Ferroelastic domain walls (DWs) underpin key functionalities in complex oxides. In free-standing ferroic thin films, where elastic interactions are highly thickness dependent, understanding DW behaviour across length scales and external…

We show that the temporal fluctuations $\Delta H(t)$ of the threshold driving field $H(t)$, which triggers an avalanche in slowly driven disordered ferromagnets with many domains, exhibit long-range correlations in space and time. The…

In this thesis I discuss analytical approaches to disordered systems using field theory. Disordered systems are characterized by a random energy landscape due to heterogeneities, which remains fixed on the time scales of the phenomena…

We study the ultra slow domain wall motion in ferromagnetic thin films driven by a weak magnetic field. Using time resolved magneto-optical Kerr effect microscopy, we access to the statistics of the intermittent thermally activated domain…

We simulate field-induced nucleation and switching of domains in a three-dimensional model of ferroelectrics with quenched disorder and varying domain sizes. We study (1) bursts of the switching current at slow driving along the hysteresis…

Domain wall dynamics in ferromagnets is complicated by internal degrees of freedom of the domain walls. We develop a model of domain walls in disordered thin films with perpendicular magnetic anisotropy capturing such features, and use it…

This study numerically investigates magnetisation reversal processes driven by an external magnetic field in three-dimensional antiferromagnetic spin models with weak random field disorder. Considering an extremely weak disorder and low…

We report the measurement of multivariable scaling functions for the temporal average shape of Barkhausen noise avalanches, and show that they are consistent with the predictions of simple mean-field theories. We bypass the confounding…

We study Barkhausen noise in a diluted two-dimensional Ising model with the extended domain wall and weak random fields occurring due to coarse graining. We report two types of scaling behavior corresponding to (a) low disorder regime where…

Magnetic domain walls display universal, disorder-controlled elastic dynamics at low drive, and texture-governed free motion at high drive. Here, we establish the crossover mechanism between these two regimes. Using experiments in ultrathin…

Two magnets in relative motion interact through their dipolar fields, making individual magnetic moments dynamically adapt to the changes in the energy landscape and bringing about collective magnetization dynamics. Some of the energy of…

Domain walls in ferroelectrics exhibit a plethora of phases and functionalities not found in the bulk. The interplay of electrostatic, chemical, topological, and distortive inhomogeneities at the walls can be so complex, however, that this…

The effect of impurity and domain-wall scattering on the electrical conductivity of disordered mesoscopic magnetic thin films is studied by use of computer simulation. The results indicate a reduction of resistivity due to a domain wall,…

Using multiscaling analysis, we compare the characteristic roughening of ferroelectric domain walls in PZT thin films with numerical simulations of weakly pinned one-dimensional interfaces. Although at length scales up to a length scale…

We investigate dynamic hysteresis in ferromagnetic thin films with zigzag domain walls. We introduce a discrete model describing the motion of a wall in a disordered ferromagnet with in-plane magnetization, driven by an external magnetic…

We present an experimental study of the changes generated on the electrical resistance $R(T)$ of epitaxial Cr thin films by the transformation of quantized spin density wave domains as the temperature is changed. A characteristic resistance…

We report first principle numerical study of domain wall (DW) depinning in two-dimensional magnetic film, which is modeled by 2D random-field Ising system with the dipole-dipole interaction. We observe nonconventional activation-type motion…