2003/05/31 by Sanjeev Kumar, Pinaki Majumdar · 1 citation
Materials Science · Physics and Astronomy · #Atomic and Subatomic Physics Research #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.str-el
paper · pdf · doi:10.1140/epjb/e2005-00261-9
published as Eur. Phys. J. B, vol 46, 315 (2005) · 11 pages revtex. Final version, to appear in EPJB
arxiv created 2005/06/02 · openalex publication_date 2005/08/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose a scheme for constructing classical spin Hamiltonians from Hunds coupled spin-fermion models in the limit JH/t → \infinity. The strong coupling between fermions and the core spins requires self-consistent calculation of the effective exchange in the model, either in the presence of inhomogeneities or with changing temperature. In this paper we establish the formalism and discuss results mainly on the ``clean'' double exchange model, with self consistently renormalised couplings, and compare our results with exact simulations. Our method allows access to system sizes much beyond the reach of exact simulations, and we can study transport and optical properties of the model without artificial broadening. The method discussed here forms the foundation of our papers Phys. Rev. Lett. 91, 246602 (2003), and Phys. Rev. Lett. 92, 126602 (2004).