Related papers: Ferromagnetism and disorder: A dynamical mean-fiel…
The subtle interplay of randomness and quantum fluctuations at low temperatures gives rise to a plethora of unconventional phenomena in systems ranging from quantum magnets and correlated electron materials to ultracold atomic gases.…
We formulate the Dynamical Mean Field Approximation equations for the double-exchange system with quenched disorder for arbitrary relation between Hund exchange coupling and electron band width. Close to the ferromagnetic-paramagnetic…
The influence of substitutional disorder on the transport properties of heavy-fermion systems is investigated. We extend the dynamical mean-field theory treatment of the periodic Anderson model (PAM) to a coherent-potential approximation…
We investigate the zero-temperature ferromagnetic behavior of a two-component repulsive Fermi gas in the presence of a correlated random field that represents an optical speckle pattern. The density is tuned so that the (noninteracting)…
We investigate the paramagnetic periodic Anderson model using the dynamical mean-field theory in combination with the modified perturbation theory which interpolates between the weak and strong coupling limits. For the symmetric PAM, the…
A detailed study of the paramagnetic to ferromagnetic phase transition in the one-band Hubbard model in the presence of binary alloy disorder is presented. The influence of the disorder (with concentration $x$ and $1-x$ of the two alloy…
We calculate magnetic couplings in the $J_{pd}$ model for dilute magnets, in order both to identify the relevant parameters which control ferromagnetism and also to bridge the gap between first principle calculations and model approaches.…
The electronic structures of fcc Ce are calculated for large supercells with varying disorder by use of density-functional theory. Thermal disorder induces fluctuations of the amplitude of the magnetic moments and an increase the average…
The parallel-tempering method has been applied to numerically study the thermodynamic behavior of a three-dimensional disordered antiferromagnetic Ising model with random fields at spin concentrations corresponding to regions of both weak…
Using the Density Matrix Renormalization Group, we study metallic ferromagnetism in a one-dimensional copper-oxide model which contains one oxygen p-orbital and one copper d-orbital. The parameters for the d-p model can be chosen so that it…
We present a detailed, quantitative study of the competition between interaction- and disorder-induced effects in electronic systems. For this the Anderson-Hubbard model with diagonal disorder is investigated analytically and by Quantum…
We present a Hartree-Fock study of the competition between disorder and interactions in quantum Hall ferromagnets near $\nu=1$. We find that the ground state at $\nu=1$ evolves with increasing interaction strength from a quasi-metallic…
We study the effect of disorder on the order parameter equation and transition temperature of a Pomeranchuk-type Fermi-surface instability using replica mean field theory. We consider the example of a phase transition to a $d_{x^2 +y^2}$…
Random fields disorder Ising ferromagnets by aligning single spins in the direction of the random field in three space dimensions, or by flipping large ferromagnetic domains at dimensions two and below. While the former requires random…
We theoretically investigate impurity correlation and magnetic clustering effects on the long-range ferromagnetic ordering in diluted magnetic semiconductors, such as $\textrm{Ga}_{1-x}\textrm{Mn}_{x}\textrm{As}$, using analytical arguments…
The magnetic ground state phase diagram of the disordered Hubbard model at half-filling is computed in dynamical mean-field theory supplemented with the spin resolved, typical local density of states. The competition between many-body…
We study the two-dimensional paramagnetic Anderson-Hubbard model using an extension of dynamical mean-field theory that allows us to treat disorder and strong electronic correlations on equal footing. We investigate the scaling of the…
The influence of configurational disorder on the magnetic properties of diluted Heisenberg spin systems is studied with regard to the ferromagnetic stability of diluted magnetic semiconductors. The equation of motion of the magnon Green's…
The mean field approximation is used to investigate the general features of the dynamics of a two-level atom in a ferromagnetic lattice close to the Curie temperature. Various analytical and numerical results are obtained. We first…
We present a theory based on Green's function formalism to study magnetism in disordered Heisenberg systems with long range exchange integrals. Disordered Green's function are decoupled within Tyablicov scheme and solved with a CPA method.…