Spin-charge separation and topological phase transitions in Aharonov-Bohm rings of interacting electrons

B. NORMAND, K. HALLBERG, A. ALIGIA AND A. KAMPF

INTERNATIONAL JOURNAL OF MODERN PHYSICS B

World Scientific

Lugar: Singapur; Año: 2006 vol. 20 p. 2651 - 2655

0217-9792

We investigate the properties of strongly correlated electronic models on a flux-threaded ring connected to semi-infinte free-electron leads. The interference pattern of such an Aharonvo-Bohm ring shows sharp dips at certain flux values, determined by the filling, which are a consequence of spin-charge separation. For a ring described by the half-filled ionic Hubbard model, the weight of the first cionductance peak as a function of gate voltage or external flux allows one to identify the topological charge transition between a correlated insulator and a band insulator.