Numerical Renormalization Group Analysis of Interacting Quantum Dots

dc.creatorHofstetter, Walter
dc.date2001-04-17
dc.date.accessioned2026-07-25T21:50:41Z
dc.descriptionWilson's Numerical Renormalization Group (NRG) is so far the only nonperturbative technique that can reliably access low-energy properties of quantum impurity systems. We present a recent extension of the method, the DM-NRG, which yields highly accurate results for dynamical quantities at arbitrary frequencies and temperatures. As an application, we determine the spectrum of a quantum dot in an external magnetic field. Furthermore, we discuss magnetic impurities with orbital degeneracy, which have been inferred in recent experiments on quantum dots in an Aharonov-Bohm geometry. It is demonstrated that for spinless electrons, interference between neighbouring levels sets the low-energy scale of the system. Switching on an external field leads to a remarkable crossover into a regime dominated by orbital Kondo screening. We predict that the broadening-induced level splitting should be clearly visible in measurements of the optical absorption power. A more general model including the electron spin is studied within an extended two-band NRG procedure. We observe competition between interference and Kondo screening, similar to the situation in two-impurity models (RKKY).
dc.descriptionInvited talk at the DPG spring meeting 2001, to appear in Advances in Solid State Physics 41
dc.identifierhttps://arxiv.org/abs/cond-mat/0104297
dc.identifierhttp://arxiv.org/abs/cond-mat/0104297
dc.identifierAdvances in Solid State Physics 41, 27 (2001)
dc.identifier.urihttps://dspace.dare.co.zw/handle/123456789/83420
dc.subjectMesoscale and Nanoscale Physics
dc.subjectStrongly Correlated Electrons
dc.titleNumerical Renormalization Group Analysis of Interacting Quantum Dots
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