相关论文: Two Ferromagnetic Phases in Spin-Fermion Systems
We study the theoretical model of a ferromagnetic semiconductor as a system of randomly distributed Ising spins with a long-range exchange interaction. Using the density-of-states approach, we analytically obtain the magnetic susceptibility…
We show using extensive simulation results and physical arguments that an Ising system on a two dimensional square lattice, having interactions of random sign between first neighbors and ferromagnetic interactions between second neighbors,…
We study numerically the thermodynamic properties of the spin nematic phases in a magnetic field in the spin-1 bilinear-biquadratic model. When the field is applied, the phase transition temperature once goes up and then decreases rapidly…
Ferromagnetism is an exciting phase of matter exhibiting strongly correlated electron behavior and a standard example of spontaneously broken rotational symmetry: below the Curie temperature, atomic magnets in an isotropic single-domain…
The magnetic properties of a variety of materials with promise for technological applications have been described by models in which fermions are coupled to local moment spins. Monte Carlo studies of such models usually ignore…
Can a gas of spin-up and spin-down fermions become ferromagnetic due to repulsive interactions? This question which has not yet found a definitive theoretical answer was addressed in an experiment with an ultracold two-component Fermi gas.…
We unravel the dynamical stability of a fully polarized one-dimensional ultracold few-fermion spin-1/2 gas subjected to inhomogeneous driving of the itinerant spins. Despite the unstable character of the total spin-polarization the…
We studied magnetic properties of the double exchange (DE) model with S=1/2 localized spins at T=0, using exact diagonalization in the framework of the dynamical mean field theory. Obtained phase diagram contains ferromagnetic,…
We derive the phase structure and thermodynamics of ferromagnets consisting of elementary magnets carrying the adjoint representation of $SU(N)$ and coupled through two-body quadratic interactions. Such systems have a continuous $SU(N)$…
We report results of the first muon-spin rotation measurements performed on the low carrier density ferromagnet EuB$_6$. The ferromagnetic state is reached via two magnetic transitions at $T_{\rm m}=16.5$ K and $T_{\rm c}=12.6$ K. Two…
We propose an experiment to explore the magnetic phase transitions in interacting fermionic Hubbard systems, and describe how to obtain the ferromagnetic phase diagram of itinerant electron systems from these observations. In addition…
The spectral properties of itinerant 2D systems with (nearly) ferromagnetic ground state are studied within the spin-fermion and the classical s-d exchange models. While the former model describes the effect of collective magnetic…
We measure thermodynamic magnetization of a low-disordered, strongly correlated two-dimensional electron system in silicon. Pauli spin susceptibility is observed to grow critically at low electron densities - behavior that is characteristic…
We consider a superconductor-ferromagnet (S/F) structure and assume that above the superconducting transition temperature $T_{c}$ the magnetic moment exists only in F. {In a simple model of the ferromagnet (the exchange field is of the…
The dynamical response of an Ising ferromagnet to a plane polarised standing magnetic field wave is modelled and studied here by Monte Carlo simulation in two dimensions. The amplitude of standing magnetic wave is modulated along the…
We explore a transverse-field Ising model that exhibits both spontaneous symmetry-breaking and eigenstate thermalization. Within its ferromagnetic phase, the exact eigenstates of the Hamiltonian of any large but finite-sized system are all…
We report thermodynamic magnetization measurements of two-dimensional electrons in several high mobility Si metal-oxide-semiconductor field-effect transistors. We provide evidence for an easily polarizable electron state in a wide density…
We investigate the relaxation of homogeneous Ising ferromagnets on finite lattices with zero-temperature spin-flip dynamics. On the square lattice, a frozen two-stripe state is apparently reached approximately 1/4 of the time, while the…
The phase diagram of several itinerant ferromagnets reveals the common feature. The phase transition temperature decreases with pressure increase and reaches zero value at some critical pressure $P_c$ such that at low enough temperatures…
At temperatures well below the Fermi temperature $T_F$, the coupling of magnetic fluctuations to particle-hole excitations in a two-component Fermi gas makes the transition to itinerant ferromagnetism a first order phase transition. This…