Real-time nonequilibrium dynamics of quantum glassy systems

被引:76
作者
Cugliandolo, LF
Lozano, G
机构
[1] Ecole Normale Super, Phys Theor Lab, CNRS, Unite Propre, F-75231 Paris 05, France
[2] Univ Paris Sud, Ecole Normale Super, Phys Theor Lab, F-75231 Paris 05, France
[3] Phys Theor & Hautes Energies Lab, F-75005 Paris, France
[4] Univ Paris Sud, Inst Phys Nucl, Div Phys Theor, Univ Paris 11,CNRS,Unite Rech, F-91406 Orsay, France
[5] Univ Paris Sud, Inst Phys Nucl, Div Phys Theor, Univ Paris 06,CNRS,Unite Rech, F-91406 Orsay, France
来源
PHYSICAL REVIEW B | 1999年 / 59卷 / 02期
关键词
D O I
10.1103/PhysRevB.59.915
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We develop a systematic analytic approach to aging effects in quantum disordered systems in contact with an environment. Within the closed-time path-integral formalism we include dissipation by coupling the system to a set of independent harmonic oscillators that mimic a quantum thermal bath. After integrating over the bath variables and averaging over disorder we obtain an effective action that determines the real-time dynamics of the system. The classical limit yields the Martin-Siggia-Rose generating functional associated to a colored noise. We apply this general formalism to a prototype model related to the p spin glass. We show that the model has a dynamic phase transition separating the paramagnetic from the spin-glass phase and that quantum fluctuations depress the transition temperature until a quantum critical point is reached. We show that the dynamics in the paramagnetic phase is stationary but presents an interesting crossover from a region controlled by the classical critical point to another one controlled by the quantum critical point. The most characteristic property of the dynamics in a glassy phase, namely, aging, survives the quantum fluctuations. In the subcritical region the quantum fluctuation-dissipation theorem is modified in a way that is consistent with the notion of effective temperatures introduced for the classical case. We discuss these results in connection with recent experiments in dipolar quantum spin glasses and the relevance of the effective temperatures with respect to the understanding of the low-temperature dynamics. [S0163-1829(99)14001-3].
引用
收藏
页码:915 / 942
页数:28
相关论文
共 137 条
[1]   New results about aging in an orientational glass [J].
Alberici, F ;
Doussineau, P ;
Levelut, A .
EUROPHYSICS LETTERS, 1997, 39 (03) :329-334
[2]  
Alberici F, 1997, J PHYS I, V7, P329, DOI 10.1051/jp1:1997148
[3]  
ALBERICIKIOUS F, CONDMAT9805208
[4]  
[Anonymous], PHYS REP
[5]  
[Anonymous], HEPPH9701304
[6]  
[Anonymous], ANN REV COMPUTATIONA
[7]   Monte Carlo simulations of the violation of the fluctuation-dissipation theorem in domain growth processes [J].
Barrat, A .
PHYSICAL REVIEW E, 1998, 57 (03) :3629-3632
[8]  
BARRAT JL, CONDMAT9806027
[9]  
Bhatt R. N., 1997, SPIN GLASSES RANDOM
[10]   SPIN-GLASSES - EXPERIMENTAL FACTS, THEORETICAL CONCEPTS, AND OPEN QUESTIONS [J].
BINDER, K ;
YOUNG, AP .
REVIEWS OF MODERN PHYSICS, 1986, 58 (04) :801-976