2006/12/13 by Rok Žitko, Rok Zitko, J. Bonča +1
Engineering · Physics and Astronomy · #Molecular Junctions and Nanostructures #Quantum and electron transport phenomena #Semiconductor materials and devices #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.74.224411
published as Phys. Rev. B 74, 224411 (2006) · 13 pages, 11 figures
openalex publication_date 2006/12/13 · arxiv created 2006/12/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the spin-charge separation in a Kondo-like model for an impurity with a spin and a charge (isospin) degree of freedom coupled to a single conduction channel (the ``spin-charge'' Kondo model). We show that the spin and charge Kondo effects can occur simultaneously at any coupling strength. In the continuum (wide-band or weak coupling) limit, the Kondo screening in each sector is independent, while at finite bandwidth and strong coupling the lattice effects lead to a renormalization of the effective Kondo exchange constants; nevertheless, universal spin and charge Kondo effects still occur. We find similar behavior in the two-impurity Anderson model with positive and negative electron-electron interaction and in the two-impurity Anderson-Holstein model with a single phonon mode. We comment on the applicability of such models to describe the conductance of deformable molecules with a local magnetic moment.