Transverse magnetoresistance in spin-glass alloys

The scattering of the conduction electrons by magnetic ions in the spin-glass phase in the presence of a magnetic field has been investigated. The transverse magnetoresistance of spinglasses has been calculated using the method of the double-time Green's function and the Kubo-Greenwood formula. The higher-order Green's functions have been decoupled into the lower-order Green's functions using Nagaoka's decoupling approximation. In the first approximation we have neglected the correlation function describing the quasibound states between the conduction electron and the impurity spin. The self-energy of the Green's function has been obtained to the second order in normal and exchange interactions $V_0$ and $J$, respectively. It is found that the self-energy consists of two parts: one involving the spin-glass order parameter $Q$ and the other spin-deviation correlation function. An expression for the transverse magnetoresistance has been obtained by evaluating the relaxation time at the Fermi surface.