Effect of charge-spin separation on the conductance through interacting low-dimensional rings

JULIAN RINCON, K. HALLBERG, AND A.A. ALIGIA ́

PHYSICA B - CONDENSED MATTER

ELSEVIER SCIENCE BV

Año: 2009 vol. 404 p. 3147 - 3150

0921-4526

<!-- @page { size: 21cm 29.7cm; margin: 2cm } P { margin-bottom: 0.21cm } --> We calculate the conductance through Aharonov?Bohm chain and ladder rings pierced by a magnetic flux which couples with the charge degrees of freedom. The system is weakly coupled to two leads and contains strongly interacting electrons modeled by the prototypical t À J and Hubbard models. For a wide range of parameters we observe characteristic dips in the conductance as a function of magnetic flux which are a signature of spin and charge separation. We also show how the dips evolve when the parameters of the models depart from the ideal case of total spin?charge separation. The ladder ring can be mapped onto an effective model for large anisotropy which can be easily analyzed. These results open the possibility of observing this peculiar many-body phenomenon in anisotropic ladder systems and in real nanoscopic devices.