相关论文: Bump of sound velocity in dense 2-color QCD

We obtain the equation of state (EoS) for two-color QCD at low temperature and high density from the lattice Monte Carlo simulation. We find that the velocity of sound exceeds the relativistic limit ($c_s^2/c^2=1/3$) after BEC-BCS crossover…

We investigated the phase structure and the equation of state (EoS) for dense two-color QCD at low temperatures using the lattice Monte Carlo simulations. A rich phase structure below the pseudo-critical temperature $T_c$ as a function of…

We study zero temperature equations of state (EOS) in isospin QCD within a quark-meson model which is renormalizable and hence eliminates high density artifacts in models with the ultraviolet cutoff (e.g., NJL models). The model exhibits a…

We review recent works on the Monte Carlo simulations of dense two-color QCD (QC$_2$D) by focusing on the phase diagram, the equation of state, and the sound velocity at nonzero quark chemical potential. A possible upper bound of the sound…

We map out the critical velocity in the crossover from Bose-Einstein condensation (BEC) to Bardeen-Cooper-Schrieffer superfluidity with ultracold $^{6}$Li gases. A small attractive potential is dragged along lines of constant column…

We investigate the quark contribution to the equation of state (EOS) of the isospin QCD matter using the two-flavor quark meson model at finite isospin density. This model includes the quark degrees of freedom through the lowest order of…

We investigate the excitation spectrum and compressibility of a dipolar Bose-Einstein condensate in an infinite tube potential in the parameter regime where the transition between superfluid and supersolid phases occurs. Our study focuses…

We present results for the equation of state in (2+1)-flavor QCD using the highly improved staggered quark action and lattices with temporal extent $N_{\tau}=6,~8,~10$, and $12$. We show that these data can be reliably extrapolated to the…

We discuss stiffening of dense matter in two color QCD (QC$_2$D) where hadrons are mesons and diquark baryons. We study two models which describe a transition of matter from the Bose-Einstein-Condensation regime at low density to the…

We study finite-temperature properties of a two-dimensional superfluid made of ultracold alkali-metal atoms in the BCS-BEC crossover. We investigate the region below the critical temperature $T_{BKT}$ of the Berezinskii-Kosterlitz-Thouless…

We present measurements of the critical velocity for vortex shedding in a highly oblate Bose-Einstein condensate with a moving repulsive Gaussian laser beam. As a function of the barrier height $V_0$, the critical velocity $v_c$ shows a dip…

We present recent updates and results from QC$_2$D (Two Colour QCD) simulations at non-zero baryon density, including progress toward determining the speed of sound.

This talk provides a summary of the results obtained by the HotQCD collaboration on the equation of state and the crossover transition in 2+1 flavor QCD. We investigate bulk thermodynamic quantities - energy density, pressure, entropy…

In superfluid systems several sound modes can be excited, as for example first and second sound in liquid helium. Here, we excite propagating and standing waves in a uniform two-dimensional Bose gas and we characterize the propagation of…

The speed of sound in QCD matter at finite temperature and density is investigated within the Polyakov loop improved Nambu--Jona-Lasinio (PNJL) model. The spinodal structure associated with the chiral first-order chiral phase transition is…

Based on the dielectric formalism in the generalised random phase approximation, we generalise the description of a Bose condensed gas to allow for a relative velocity between the superfluid and normal fluid. In this model, we determine the…

We numerically model experiments on the superfluid critical velocity of an elongated, harmonically trapped Bose-Einstein condensate as reported by [P. Engels and C. Atherton, Phys. Rev. Lett. 99, 160405 (2007)]. These experiments swept an…

The final stage of Bose-Einstein condensation in a large volume occurs through coarsening--growth of individual correlated patches. We present analytical arguments and numerical evidence that in the momentum space this growth corresponds to…

Disorder modifies the sound-wave excitation spectrum of Bose-Einstein condensates. We consider the classical hydrodynamic limit, where the disorder correlation length is much longer than the condensate healing length. By perturbation…

We systematically investigate the speed of sound in QCD matter under different conditions in the grand canonical ensemble within the Polyakov loop improved Nambu--Jona-Lasinio (PNJL) model. The numerical results indicate that the dependence…