Statut | Confirmé |
Série | CONDMAT-ENS |
Domaines | cond-mat |
Date | Mardi 5 Avril 2011 |
Heure | 10:45 |
Institut | LPS/ENS |
Salle | T4/5 (3e étage) |
Nom de l'orateur | Andreanov |
Prenom de l'orateur | Alexei |
Addresse email de l'orateur | andreanov [dot] alexei [at] ictp [dot] it |
Institution de l'orateur | ICTP, Trieste |
Titre | Quantun spin glass at T=0 |
Résumé | Quantum spin glasses are glassy systems where both thermal and quantum fluctuations can drive the transition. The generic interest to these systems is motivated by a question "How quantum fluctuations affect the glass phase: can they destroy it ? How do they affect its properties ?" We have studied a transverse field Ising spin glass [2,3] where the strength of quantum fluctuations is tuned by a transverse field. The model possesses a paramagnetic and a glass phases [2,3]. The presence of the quantum phase transition is well established however little is known about the nature of the glass phase. We have proved that the entire glass phase is critical and gapless giving rise to specific low lying excitations which can be interpreted as an Ohmic bath of oscillators. For small transverse fields we have also discovered a fixed point of the Parisi equations identical to that uncovered by Pankov in classical spin glasses[3]. Refs: 1. A. Bray and M. Moore, J. Phys. C 13, L655 (1980). 2. J. Miller and D. Huse, PRL 70, 20 (1993) 3147. 3. M.J. Rozenberg and D.R. Grempel, PRL 81, 12 (1998) 2550. 4. S. Pankov, PRL 96, 197204 (2006). |
Numéro de preprint arXiv | |
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