Transition temperature and specific heat jump of a proximity effect sandwich containing local spin fluctuations

Abstract

The renormalization equations for a proximity effect sandwich containing local spin fluctuations in the normal layer are solved when the temperature is close to Tc. Expressions for the transition temperature and the specific heat jump at Tc are obtained. This decrease of the transition temperature as a function of the thickness of the normal layer is seen in the appropriate limits to be similar to what is expected of sandwiches containing nonmagnetic localized states and of sandwiches containing well-defined magnetic moments. Since no reentrant behavior is seen for the magnetic case, the specific heat jump for this case does not show the increase at low temperatures recently obtained by Kaiser and Keleher for sandwiches containing Kondo impurities. © 1985 Plenum Publishing Corporation.