相关论文: Energetic analysis of disorder effects in an artif…
We present a numerical study on a disordered artificial spin-ice system which interpolates between the long-range ordered square ice and the fully degenerate shakti ice. Starting from the square-ice geometry, disorder is implemented by…
The field-induced dynamics of artificial spin ice are determined in part by interactions between magnetic islands, and the switching characteristics of each island. Disorder in either of these affects the response to applied fields.…
Quenched disorder affects how non-equilibrium systems respond to driving. In the context of artificial spin ice, an athermal system comprised of geometrically frustrated classical Ising spins with a two-fold degenerate ground state, we give…
We report a novel approach to the question of whether and how the ground state can be achieved in square artificial spin ices where frustration is incomplete. We identify two types of disorder: quenched disorder in the island response to…
We study the effects of disorder in two-dimensional quantum antiferromagnets on a square lattice, within the nonlinear sigma model approach, by using of a random distribution of spin stiffnesses or zero-temperature-spin-gaps, respectively,…
We have performed a systematic study of the effects of field strength and quenched disorder on the driven dynamics of square artificial spin ice. We construct a network representation of the configurational phase space, where nodes…
The effect of quenched (frozen) disorder on the collective motion of active particles is analyzed. We find that active polar systems are far more robust against quenched disorder than equilibrium ferromagnets. Long ranged order (a non-zero…
We report an artificial geometrically frustrated magnet based on an array of lithographically fabricated single-domain ferromagnetic islands. The islands are arranged such that the dipole interactions create a two-dimensional analogue to…
Extensive Monte Carlo simulations are used to investigate the stability of the ferromagnetic ground state in three-dimensional systems of Ising dipoles with added quenched disorder. These systems model the collective ferromagnetic order…
The results of a numerical study of an ordered substitution of a double-segment into the unit cell of square artificial spin ice are presented. Each pattern vertex has three magnetic moment configurations that compete to form a magnetic…
We have studied the temperature and magnetic field dependence of the total magnetic moment of large-area permalloy artificial square spin ice arrays. The temperature dependence and hysteresis behavior are consistent with the coherent…
We report a magneto-optical Kerr effect study of the collective magnetic response of artificial square spin ice, a lithographically-defined array of single-domain ferromagnetic islands. We find that the anisotropic inter-island interactions…
The effect of quenched (frozen) orientational disorder on the collective motion of active particles is analyzed. We find that, as with annealed disorder (Langevin noise), active polar systems are far more robust against quenched disorder…
The switching field distribution within arrays of single-domain ferromagnetic islands incorpo- rates both island-island interactions and quenched disorder in island geometry. Separating these two contributions is important for disentangling…
We present results of a numerical mean field treatment of interacting spins and carriers in doped diluted magnetic semiconductors, which takes into account the positional disorder present in these alloy systems. Disorder is found to enhance…
Small amplitude dipolar oscillations are considered in artificial spin ice on a square lattice in two dimensions. The net magnetic moment of each elongated magnetic island in the spin ice is assumed to have Heisenberg-like dynamics. Each…
We report here the results of micromagnetic simulations of square artificial spin ice (ASI) systems with defects. The defects are introduced by misaligning of a nanomagnet at the vertex. In these defective systems, we are able to stabilize…
Artificial spin ices are arrays of correlated nano-scale magnetic islands that prove an excellent playground in which to study the role of topology in critical phenomena. Here, we investigate a continuum of spin ice geometries,…
After removal of an applied magnetic field, artificial square spin ice can be left in a metastable remanent state, with nonzero residual magnetization and excess energy above the ground state. Using a model of magnetic islands with dipoles…
In order to explain and predict the properties of many physical systems, it is essential to understand the interplay of different energy-scales. Here we present investigations of the magnetic order in thermalised artificial spin ice…