We study the character change of the pionic condensation at finite isospin chemical potential \mu_\mathrm{ I} by adopting the linear sigma model as a non-local interaction between quarks. At low |\mu_\mathrm{ I}| the condensation is purely bosonic, then the Cooper pairing around the Fermi surface grows gradually as |\mu_\mathrm{ I}| increases. This q-\bar q pairing is weakly coupled in comparison with the case of the q-q pairing that leads to color superconductivity.
Categories: hep-ph cond-mat.quant-gas cond-mat.supr-con nucl-th