相关论文: Why spin ice obeys the ice rules
We present a first-principles investigation of the spin-ice state in Dy$_2$Ti$_2$O$_7$ using a magnetic source-free exchange and correlation functional, implemented in the Castep electronic-structure code. By comparing results from the…
Dipolar-octupolar (DO) pyrochlore systems Ce$_2$(Zr,Sn,Hf)$_2$O$_7$ have garnered much attention as recent investigations suggest that they may stabilize a novel quantum spin ice (QSI), a quantum spin liquid (QSL) with an emergent $U(1)$…
We consider N initially disentangled spins, embedded in a ring or d-dimensional lattice of arbitrary geometry, which interact via some long--range Ising--type interaction. We investigate relations between entanglement properties of the…
Thermodynamic perturbation theory is employed to derive analytical expressions for the equilibrium linear susceptibility and specific heat of lattices of anisotropic classical spins weakly coupled by the dipole-dipole interaction. The…
We combine first principles density functional calculations with empirical relationships for the Coulomb interactions in the `monomer' model of $\kappa$-(BEDT-TTF)$_2X$. This enables us to calculate the parameters for the model of coupled…
The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the…
The Ce$_2$X$_2$O$_7$ (X=Sn, Hf, Zr) family of cubic pyrochlores has emerged as one of the most promising classes of Quantum Spin Ice candidates. However, understanding their microscopic exchange Hamiltonian and spin correlations has been…
Motivated by experiments on NiGa2S4, we discuss characteristic (finite temperature) properties of spin S = 1 quantum antiferromagnets on the triangular lattice. Several recent theoretical studies have suggested the possibility of…
New methods are presented which enables one to analyze the thermodynamics of systems with long-range interactions. Generically, such systems have entropies which are non-extensive, (do not scale with the size of the system). We show how to…
Using synchrotron X-rays and neutron diffraction we disentangle spin-lattice order in highly frustrated ZnCr$_2$O$_4$ where magnetic chromium ions occupy the vertices of regular tetrahedra. Upon cooling below 12.5 K the quandary of…
We study the low temperature dynamics in films made of molecular magnets, i. e. crystals composed of molecules having large electronic spin S in their ground state. The electronic spin dynamics is mediated by coupling to a nuclear spin…
We present a mechanism of resistivity minimum in conduction electron systems coupled with localized moments, which is distinguished from the Kondo effect. Instead of the spin-flip process in the Kondo effect, electrons are elastically…
The very low temperature properties of two pyrochlore compounds, Yb2Ti2O7 and Gd2Sn2O7, were investigated using an ensemble of microscopic and bulk techniques. In both compounds, a first order transition is evidenced, as well as spin…
We study the low temperature dynamics of the classical Heisenberg antiferromagnet with nearest neighbour interactions on the pyrochlore lattice. We present extensive results for the wavevector and frequency dependence of the dynamical…
With the recent production of polar molecules in the quantum regime, long-range dipolar interactions are expected to facilitate the understanding of strongly interacting many-body quantum systems and to realize lattice spin models for…
Recently, significant interest has emerged in fabricated systems that mimic the behavior of geometrically-frustrated materials. We present the full realization of such an artificial spin ice system on a two-dimensional kagome lattice and…
We present our analysis of a system of interacting islands of XY spins on a triangular lattice that has been introduced a few years ago by Eley et al. to account for the phenomenology in experiments on tunable arrays of proximity coupled…
One of the most remarkable examples of emergent quasi-particles, is that of the "fractionalization" of magnetic dipoles in the low energy configurations of materials known as "spin ice", into free and unconfined magnetic monopoles…
The crystal structure of hexagonal-Sr0.6Ba0.4MnO3 allows various competing superexchange interactions, leading to intriguing magnetic properties. Local structural changes modify overlapping between Mn and oxygen ions with temperature.…
Using tempered Monte Carlo simulations, we study the the spin-glass phase of dense packings of Ising dipoles pointing along random axes. We consider systems of L^3 dipoles (a) placed on the sites of a simple cubic lattice with lattice…