相关论文: Universal dynamics of magnetic monopoles in two-di…

We study an artificial spin ice system consisting of two identical layers separated by a height offset $h$. For small separation, the layers are shown to attract each other, provided the whole system is in the ground state. Such an…

In Refs.[1-4] Dirac and Schwinger showed the existence of a magnetic monopole required a charge quantization condition which we write following Dirac as $\frac{eg}{4\pi\hbar}=\frac{n}{2},\; n=0,\pm 1,\; \pm 2, \ldots$. Here, $g$ is the…

It was proposed that spin ice, a class of rare earth titanates, hosts elementary excitations akin to magnetic monopoles. Recently, Bramwell and co-workers [arXiv:arXiv:0907.0956] measured the Wien effect in Dy2Ti2O7, directly probing the…

We study, by means of magnetic susceptibility and magnetic aging experiments, the nature of the glassy magnetic dynamics in arrays of Co nanoparticles, self-organized in N layers from N=1 (two-dimensional limit) up to N=20…

Artificial spin ice systems are metamaterials composed of interacting nanomagnets arranged on a lattice, exhibiting geometrical frustration and emergent phenomena such as monopole excitations. We explore magnetization dynamics and monopole…

Here we study the statistical properties of two-dimensional spin ice in its ground state by the Monte Carlo simulation method. Using a new sampling algorithm, we show that the short-range ice rule in two dimensions gives rise to long-range…

Designing and constructing model systems that embody the statistical mechanics of frustration is now possible using nanotechnology. We have arranged nanomagnets on a two-dimensional square lattice to form an artificial spin ice, and studied…

We study the low-temperature behaviour of spin ice when uniaxial pressure induces a tetragonal distortion. There is a phase transition between a Coulomb liquid and a fully magnetised phase. Unusually, it combines features of discontinuous…

In this thesis, we consider the dynamics of vortices in the easy plane insulating ferromagnet in two dimensions. In addition to the quasiparticle excitations, here spin waves or magnons, this magnetic system admits a family of vortex…

A non-Ohmic current that grows exponentially with the square root of applied electric field is well known from thermionic field emission (the Schottky effect), electrolytes (the second Wien effect) and semiconductors (the Poole-Frenkel…

The spin ice compound Dy_2Ti_2O_7 stands out as the first topological magnet in three dimensions, with its tell-tale emergent fractionalized magnetic monopole excitations. Its real-time dynamical properties have been an enigma from the very…

We investigate the temperature dependence of the spin dynamics in the pyrochlore magnet Nd$_2$Zr$_2$O$_7$ by neutron scattering experiments. At low temperature, this material undergoes a transition towards an "all in - all out"…

We study quantum spin ice in an external magnetic field applied along a $<100>$ direction. When quantum spin fluctuations are weak, elementary excitations are quantum strings with monopoles at their ends manifested as multiple spin-wave…

A rich variety of physical effects in spin dynamics arises at the interface between different magnetic materials. Engineered systems with interlaced magnetic structures have been used to implement spin transistors, memories and other…

We analyse an array of linearly extended monodomain dipoles forming square and kagome lattices. We find that its phase diagram contains two (distinct) finite-entropy kagome ice regimes - one disordered, one algebraic - as well as a…

Thermodynamic quantities and correlation functions (CFs) of the classical antiferromagnet on the kagom\'e lattice are studied for the exactly solvable infinite-component spin-vector model, D \to \infty. In this limit, the critical coupling…

The monopole picture for spin ice offers a natural description for a confounding class of materials. A paper published in Nature Physics in 2009 applied it to study the dynamical properties of these systems -- sparking intense experimental…

Artificial spin ice provides a versatile setting for emergent gauge fields and magnetic monopole excitations. Here we propose a driven-dissipative polariton realization of artificial spin ice, in which the circular polarization of each link…

This short article sets out some of the basic considerations that go into detecting the mass of quasiparticles with effective magnetic charge in solids. Effective magnetic charges may be appear as defects in particular magnetic textures. A…

The spin ice materials Ho$_{2}$Ti$_{2}$O$_{7}$ and Dy$_{2}$Ti$_{2}$O$_{7}$ are by now perhaps the best-studied classical frustrated magnets. A crucial step towards the understanding of their low temperature behaviour -- both regarding their…