Quantum phase transitions in models of coupled magnetic impurities
Publikation: Beitrag in Fachzeitschrift › Forschungsartikel › Beigetragen › Begutachtung
Beitragende
Abstract
We discuss models of interacting magnetic impurities coupled to a metallic host, which show one or more boundary quantum phase transitions where the ground-state spin changes as a function of the interimpurity couplings. The simplest example is realized by two spin-1/2 Kondo impurities coupled to a single orbital of the host. We investigate the phase diagram and crossover behavior of this model and present numerical renormalization-group results together with general arguments showing that the singlet-doublet quantum phase transition is either of first order or of the Kosterlitz-Thouless type, depending on the symmetry of the Kondo couplings. Thus we find an exponentially small energy scale within the Kondo regime, and a two-stage Kondo effect, in a single-channel situation. Connections to other models and possible applications are discussed.
Details
Originalsprache | Englisch |
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Aufsatznummer | 140405 |
Seiten (von - bis) | 1404051-1404054 |
Seitenumfang | 4 |
Fachzeitschrift | Physical Review B - Condensed Matter and Materials Physics |
Jahrgang | 65 |
Ausgabenummer | 14 |
Publikationsstatus | Veröffentlicht - 1 Apr. 2002 |
Peer-Review-Status | Ja |
Extern publiziert | Ja |