English

Quantum Critical Behavior of the Cluster Glass Phase

Disordered Systems and Neural Networks 2007-10-22 v2 Strongly Correlated Electrons

Abstract

In disordered itinerant magnets with arbitrary symmetry of the order parameter, the conventional quantum critical point between the ordered phase and the paramagnetic Fermi-liquid (PMFL) is destroyed due to the formation of an intervening cluster glass (CG) phase. In this Letter we discuss the quantum critical behavior at the CG-PMFL transition for systems with continuous symmetry. We show that fluctuations due to quantum Griffiths anomalies induce a first-order transition from the PMFL at T=0, while at higher temperatures a conventional continuous transition is restored. This behavior is a generic consequence of enhanced non-Ohmic dissipation caused by a broad distribution of energy scales within any quantum Griffiths phase in itinerant systems.

Keywords

Cite

@article{arxiv.cond-mat/0612127,
  title  = {Quantum Critical Behavior of the Cluster Glass Phase},
  author = {Matthew J. Case and V. Dobrosavljevic},
  journal= {arXiv preprint arXiv:cond-mat/0612127},
  year   = {2007}
}

Comments

v1: 4+epsilon pages, 2 figures; v2: 4 pages, 1 figure, improved discussion, version accepted to PRL