Vortex ordering in fully-frustrated superconducting systems with dice   lattice
  The structure and the degenracy of the ground state of a fully-frustrated XY-model are investigated for the case of a dice lattice geometry.   The results are applicable for the description of Josephson junction arrays and thin superconducting wire networks in the external magnetic field providing half-integer number of flux quanta per plaquette. The mechanisms of disordering of vortex pattern in such systems are briefly discussed. 
S. E. Korshunov