Related papers: Unveiling the Physics of the Mutual Interactions i…
At finite temperature we study the quantum tunneling of magnetization for a small ferromagnetic particle with the biaxial symmetry placed in a magnetic field at an arbitrary angle. We present numerical WKB exponent below the crossover…
We present a review of recent advances in the study of many-body effects in magnetic nanoparticles. Considering classical spins on a lattice coupled by the exchange interaction in the presence of the bulk and surface anisotropy, we…
The magnetic entropy change (\DeltaS), a measure of the magnetocaloric effect, in Tb5Si3, a compound exhibiting unusual positive magnetoresistance following a magnetic-field-induced transition below magnetic transition temperature (~ 69 K),…
It is argued that a typical many body energy eigenstate has a well defined thermodynamic entropy and that individual eigenstates possess thermodynamic characteristics analogous to those of generic isolated systems. We examine large systems…
The magnetocaloric effect or "magnetic Gr\"uneisen ratio" $\Gamma_H=T^{-1}(dT/dH)_S$ quantifies the cooling or heating of a material when an applied magnetic field is changed under adiabatic conditions. Recently this property has attracted…
The one-dimensional Ising model in an external magnetic field with uniform long-range interactions and random short-range interactions satisfying bimodal annealed distributions is studied. This generalizes the random model discussed by…
Quasiparticle excitations and associated phenomena of energy and momentum transfer rates have been calculated in terms of the drag and the diffusion coefficients exposing clearly the dominance of the magnetic interaction over its electric…
We study the effect of a very strong homogeneous magnetic field B on the thermal deconfinement transition within the simplest phenomenological approach: the MIT bag pressure for the quark- gluon plasma and a gas of pions for the hadronic…
We study the thermodynamics of nonabelian ferromagnets consisting of atoms in the fundamental representation of $SU(N)$ and interacting with two-body and three-body interactions. Using a mean field approach, we uncover an intricate phase…
We study the thermodynamics of the Hamiltonian Mean Field (HMF) model with an external potential playing the role of a "magnetic field". If we consider only fully stable states, this system does not present any phase transition. However, if…
A systematic study of the effect of magnetic field (h) on Hubbard model has been carried out at half filling within dynamical mean field theory. In agreement with previous studies, we find a zero temperature itinerant metamagnetic…
The effects of electronic correlations and orbital degeneracy on thermoelectric properties are studied within the context of multi-orbital Hubbard models on different lattices. We use dynamical mean field theory with iterative perturbation…
The transition from a many-body localized phase to a thermalizing one is a dynamical quantum phase transition which lies outside the framework of equilibrium statistical mechanics. We provide a detailed study of the critical properties of…
Effects of electron correlations on Anderson insulators have been one of the central themes for recent two decades, suggesting that the Anderson insulating phase turns into a novel insulating state referred to as many body localization…
By numerically exact calculations of spin-1/2 antiferromagnetic Heisenberg models on small clusters, we demonstrate that quantum entanglement between subsystems $A$ and $B$ in a pure ground state of a whole system $A+B$ can induce thermal…
We present an inequality that gives a lower bound on the expectation value of certain two-body interaction potentials in a general state on Fock space in terms of the corresponding expectation value for thermal equilibrium states of…
We develop a variational approach at finite temperature that incorporates many-body correlation self-consistently. The grand potential is constructed in terms of Green's function expressed by the variational parameters. We apply this…
Thermalization of an isolated quantum system has been a nontrivial problem since the early days of quantum mechanics. In generic isolated quantum systems, nonequilibrium dynamics is expected to result in thermalization, indicating the…
We numerically study a Bose-Hubbard ring of finite size with disorder containing a finite number of bosons that are subject to an on-site two-body interaction. Our results show that moderate interactions induce dynamical thermalization in…
Magnetocaloric effect (MCE) in TbCo2-xFex has been studied by dc magnetization measurements.On substituting Fe in TbCo2, not only the magnetic transition temperature is tuned to room temperature, but also the operating temperature range for…