2002/10/15 by Nobuo Furukawa, Yukitoshi Motome
Physics and Astronomy · #cond-mat.str-el #cond-mat.stat-mech
paper · pdf · doi:10.1016/s0921-4526(02)02503-6
published as Physica B: Cond. Matter 329-333, 759 (2003) · 2 pages, to be published in Physica B (Proc. to LT23)
arxiv created 2002/10/15 · arxiv updated 2009/11/30
A simple derivation of the effective spin-wave Hamiltonian for a double-exchange system with infinitely large Hund's-rule coupling is demonstrated. The formalism can be applied to models with arbitrary range of hopping as well as those with randomness. The result shows that, within the leading order of the 1/S expansion, one magnon excitation spectrum can be described by the Heisenberg model.