Quantum interface unbinding transitions

摘要: We consider interfacial phenomena accompanying bulk quantum phase transitions in presence of surface fields. On general grounds we argue that the contribution to system free energy involves a line singularities characteristic an transition, occurring below transition temperature T_c down T=0. This implies occurrence critical regime extending into finite temperatures and located within portion diagram where is ordered. Even situations, order sets discontinuously at T=0, system's behavior boundary may be controlled by divergent length scale if tricritical sufficiently low. Relying on effective model compute spatial dimensionality $d\geq 2$ extract values exponents describing 3$.