NEW RESULTS ON THE PHASE DIAGRAM OF THE FFXY MODEL: A TWISTED CFT APPROACH

The issue of the number, nature and sequence of phase transitions in the fully frustrated XY (FFXY) model is a highly non trivial one due to the complex interplay between its continuous and discrete degrees of freedom. In this contribution we attack such a problem by means of a twisted conformal field theory (CFT) approach¹ and show how it gives rise to the U(1) ⊗ Z₂ symmetry and to the whole spectrum of excitations of the FFXY model.²