Inhomogeneous ferromagnetism and unconventional charge dynamics in disordered double exchange magnets.
We solve the double exchange model in the presence of arbitrary substitutional disorder by using a self-consistently generated effective Hamiltonian for the spin degrees of freedom. The magnetic properties are studied through classical Monte Carlo while the effective exchange, D(ij), is calculated by solving the disordered fermion problem, and renormalized self-consistently with increasing temperature. We present results on the conductivity, magnetoresistance, optical response, and "real space" structure of the inhomogeneous ferromagnetic state, and compare our results with charge dynamics in disordered La1-xSrxMnO3. The large sizes, O(10(3)), accessible within our method allows a complete, controlled calculation on the disordered strongly interacting problem.
Kumar
Sanjeev
S
Harish-Chandra Research Institute, Chhatnag Road, Jhusi, Allahabad 211 019, India.
Majumdar
Pinaki
P