Evidence for Kosterlitz-Thouless-type orientational ordering of CF3Br monolayers physisorbed on graphite

Article

关键词: FRUSTRATED-XY MODEL;    PHASE-TRANSITIONS;    2 DIMENSIONS;    2-DIMENSIONAL SUPERCONDUCTORS;    SYMMETRY-BREAKING;    MONTE-CARLO;    HE-4 FILMS;    C2CL2F4;   

DOI  :  10.1103/PhysRevB.65.165411

来源: SCIE

【 摘 要 】

Monolayers of the halomethane CF3Br adsorbed on graphite have been investigated by x-ray diffraction. The layers crystallize in a commensurate triangular lattice. On cooling they approach a three-sublattice antiferroelectric pattern of the in-plane components of the dipole moments. The ordering is not consistent with a conventional phase transition, but points to Kosterlitz-Thouless behavior. It is argued that the transition is described by a six-state clock model on a triangular lattice with antiferromagnetic nearest-neighbor interactions which is studied with Monte Carlo simulations. A finite-size scaling analysis shows that the ordering transition is indeed in the KT universality class.

【 授权许可】

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