Abstract
We study the persistent current of a mesoscopic ring with an embedded quantum dot or a side-coupled quantum dot, using the finite- slave boson mean-field approach suggested by Kotliar and Ruckenstein [Phys. Rev. Lett. 57, 1362 (1986)]. The persistent current shows interesting dependence on the energy of the dot level as well as the total number of electrons (modulo 4) in the systems. In the mixed valence regime, the persistent current has a maximum value for the embedded quantum dot case, whereas it shows sharp transition between plateaus of diamagnetic and paramagnetic states for the side-coupled quantum dot case. The Kondo effects on the persistent current are also investigated.
- Received 17 October 2002
DOI:https://doi.org/10.1103/PhysRevB.67.195327
©2003 American Physical Society