Aging effects in the nonequilibrium quantum spin glass in weak magnetic fields

Autor: E. V. Gazeeva, I. R. Khaibutdinova, G. P. Chugunova, G. Buziello, R. V. Saburova
Rok vydání: 2006
Předmět:
Zdroj: The Physics of Metals and Metallography. 102:244-252
ISSN: 1555-6190
0031-918X
DOI: 10.1134/s0031918x0609002x
Popis: This work is devoted to a theoretical study of effects of aging in a disordered quantum system being in contact with an interior surroundings and subject to the influence of external alternating fields. The dissipation is realized via coupling with a set of independent harmonic oscillators, which imitate a quantum thermostat (bath), and with an external field. Using the formalism of closed-path integrals, dynamic equations are derived for the autocorrelation and linear-response functions. The dependences of correlation, response, and integrated-response functions on temperature, waiting time, and quantum parameter are studied. The effect of external fields on the behavior of these functions is analyzed. A qualitative agreement with experimental data have been found.
Databáze: OpenAIRE
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