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Register a new userMetallic spin-glasses beyond mean-field: An approach to the impurity-concentration dependence of the freezing temperature
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Added by
Eduardo Cuervo Reyes
Publication date
2012
fields
Physics
and research's language is
English
Authors
Eduardo Cuervo-Reyes
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A relation between the freezing temperature ($T^{}_{rm g}$) and the exchange couplings ($J^{}_{ij}$) in metallic spin-glasses is derived, taking the spin-correlations ($G^{}_{ij}$) into account. This approach does not involve a disorder-average. The expansion of the correlations to first order in $J^{}_{ij}/T^{}_{rm g}$ leads to the molecular-field result from Thouless-Anderson-Palmer. Employing the current theory of the spin-interaction in disordered metals, an equation for $T^{}_{rm g}$ as a function of the concentration of impurities is obtained, which reproduces the available data from {sl Au}Fe, {sl Ag}Mn, and {sl Cu}Mn alloys well.
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