nbrayali's bec [8 articles]

Abstract

Using many-body results available from diagrammatic and ab initio Monte Carlo calculations we analyze the phase diagram $μ=(μa+\mda)/2$ versus $h=(μa-\mda)/2$ of a unitary Fermi gas at zero temperature with population imbalance and unequal masses. We identify different regions where the gas is superfluid, partially polarized or fully polarized and determine the corresponding coexistence conditions. The asymmetry in the phase diagram, caused by the mass imbalance, and its effect on the Chandrasekhar-Clogston limit for the critical polarization are explicitly discussed. The equation of state of the superfluid and normal ...

Abstract

The proximity effect in superfluid $^3$He partly filled with high porosity aerogel is discussed. This system can be regarded as a dirty Fermi liquid/spin-triplet p-wave superfluid junction. Our attention is mainly paid to the case when the dirty layer is in the normal state owing to the impurity pair-breaking effect by the aerogel. We use the quasiclassical Green's function to determine self-consistently the spatial variations of the p-wave order parameter and the impurity self-energy. On the basis of the fully self-consistent calculation, we analyze the spatial dependence of ...

Abstract

We consider a neutral spinor condensate moving in a periodic magnetic field. The spatially dependent magnetic field induces an effective spin dependent Lorentz force which in turn gives rise to a spin dependent Hall effect. Simulations of the Gross-Pitaevskii equation quantify the Hall effect. We discuss possible experimental realizations. ...

Abstract

By performing heat capacity, magnetocaloric effect, torque magnetometry and force magnetometry measurements up to 33 T, we have mapped out the T-H phase diagram of the S = 1/2 spin dimer compound Ba$_3$Cr$_2$O$_8$. We found evidence for field-induced magnetic order between H$_c1 = $12.52(2) T and H$_c2 ∼ $23.6 T, with the maximum transition temperature T$_c ∼ $2.7 K at H $∼$ 18 T. The transition at H$_c1$ likely corresponds to a Bose-Einstein condensation of triplons universality class, as there is an apparent preservation of U(1) symmetry in ...

Abstract

Properties of strongly interacting, two-component finite Fermi systems are discussed within the recently developed coordinate-space Hartree-Fock-Bogoliubov (HFB) code \hfbax. Two illustrative examples are presented: (i) weakly bound deformed Mg isotopes, and (ii) spin-polarized atomic condensates in a strongly deformed harmonic trap. ...

Abstract

Optical lattice experiments, with the unique potential of tuning interactions and density, have emerged as emulators of nontrivial theoretical models that are directly relevant for strongly correlated materials. However, so far the finite temperature phase diagram has not been mapped out for any strongly correlated quantum model. We propose a remarkable method for obtaining such a phase diagram for the first time directly from experiments using only the density profile in the trap as the input. We illustrate the procedure explicitly for the Bose Hubbard model, a textbook ...

Abstract

This paper examines the problem of molecule production in an atomic fermionic gas close to an s-wave Feshbach resonance by means of a magnetic field sweep through the resonance. The density of molecules at the end of the process is derived for narrow resonance and slow sweep. ...

Abstract

Building on recent neutron and NMR experiments, we investigate the field-induced exotic criticality observed in the frustrated spin-1/2 dimer compound BaCuSi2O6 using a frustrated model with two types of bilayers. A semiclassical treatment of the effective hard-core boson model shows that perfect inter-layer frustration leads to a 2D-like critical exponent phi=1 without logarithmic corrections and to a 3D low temperature phase with different but non vanishing triplet populations in both types of bilayers. These results further suggest a simple phenomenology in terms of a field-dependent transverse coupling in the ...