Magnetic-Field Dependence of the Local Electronic Structure in the Ground State of thes-dExchange System and Magnetoresistance at 0°K

Recent two publications by Y osida and Y oshimori have clarified the detailed electronic structure of the singlet collective bound state developed so far by them and by Okiji. In this paper, by means of their method, the magnetic-field dependence of the local electronic struc­ ture of the ground state is investigated. In particular, it is shown that the z-component of the spin correlation which sticks around the impurity remains unchanged even in the limit of increasing field. From this calculation, an expression for the magnetoresistance is inferred with the aid of the Friedel sum rule : 1t .d R(.d)=Rocos22- (Eo2+.J2)t/2 ' where E0 denotes the binding energy of the singlet state and .J the Zeeman energy of the free spin. It is to be noticed that this has no logarithmic field dependence. It is further shown that the relation