title: Enhanced sensitivity of the transmission phase of a quantum dot to Kondo correlations.
abstract: The strong sensitivity of the transmission phase through a quantum dot embedded into one arm of a two-wave Aharonov-Bohm interferometer to the Kondo effect is explained. The enhancement takes place because of the buildup of the exchange scattering on the dot due to Kondo correlations even much above T(K). The enhanced exchange competes with the potential scattering, which is always weak. Both cases of the Anderson impurity model and a multilevel quantum dot are considered. In the latter case in addition to the description of peculiar phase behavior a mechanism leading to ferromagnetic Kondo coupling in quantum dots is proposed.
authors.affiliation: Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands.
authors.forename: P G
authors.initials: PG
authors.lastname: Silvestrov
authors.forename: Y
authors.initials: Y
authors.lastname: Imry