Chiral multicritical points driven by isospin density in the   Ginzburg-Landau approach
  We study how a chiral tricritical point (TCP) on QCD phase diagram is affected by the imbalance of up and down quark densities (isospin density), using the generalized Ginzburg-Landau (GL) approach. The resulting phase diagram near TCP shows a rich fine structure which includes inhomogeneities of both the chiral and the charged pion condensations. It turns out that the TCP splits into multicritical points. 
Yuhei Iwata, Hiroaki Abuki and Katsuhiko Suzuki
hep-ph nucl-th