The groundstates and phases of the two-dimensional fully frustrated XY model

• The 2D Fully Frustrated NY(FFXY) class of models is shown to contain a new ground-state in addition to the checkerboard groundstate of the standard 2D NY model. The spin configuration of this additional groundstate is obtained and its connection to a broken Z(2)-symmetry explained. This means that the class of 2D FEXY models belongs within a U(1) circle times Z(2) circle times Z(2)-symmetry phase-transition representation. The phase diagram is reviewed and the central charges of the four multicritical points described. The implications for the standard 2D FFXY-model are discussed and elucidated, in particular with respect to the long standing controversy concerning the phase transitions of the standard 2D FEXY-model.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Publication and Content Type

ref (subject category)

kon (subject category)