Two Color QCD beyond the BEC regime

TL;DR

This paper reports lattice simulations of Two Color QCD at finite chemical potential, revealing a Fermi surface with Cooper pairing and evidence of deconfinement driven by quark density, challenging the simple diquark Bose condensation picture.

Contribution

It provides new lattice simulation results showing a Fermi surface and deconfinement phenomena in Two Color QCD beyond the BEC regime.

Findings

Quark density and condensate behavior suggest Fermi surface with Cooper pairing.

Evidence of screening and deconfinement due to non-zero quark density.

Results differ from the tightly bound diquark Bose condensate model.

Abstract

We present results of simulations of Two Color QCD using two flavors of Wilson quark in the fundamental representation, at non-zero quark chemical potential mu, on an 8^3x16 lattice. Results for the quark number density, quark and gluon energy densities, and superfluid condensate are qualitatively distinct from the behaviour expected on the assumption that the dominant degrees of freedom are tightly bound scalar diquarks which Bose condense; rather the scaling with mu is more suggestive of a Fermi surface disrupted by a Cooper pair condensate. We also present evidence both for screening of the static potential, and color deconfinement, arising solely as a result of a non-zero quark density.