Dual chiral density wave in quark matter

Possible manifestation of a dual chiral density wave in quark matter is discussed in relation to the chiral symmetry of QCD, which is described by a dual standing wave of the scalar and pseudo-scalar densities. It is demonstrated that quark matter is unstable for forming the dual chiral density wave at moderate densities in the Nambu-Jona-Lasinio model;accordingly the critical density for restoration of chiral symmetry becomes higher than ever considered. A unique magnetic property is also pointed out in the new phase.