Inhomogeneous Ferromagnetism and Unconventional Charge Dynamics in Disordered Double Exchange Magnets

Abstract

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, $D_{ij}$, are calculated by solving the disordered fermion problem, and renormalised self-consistently with increasing temperature. We present exact 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 La_{1-x}Sr_xMnO_3. The large sizes, $\mathcal{O}(10^3)$, accessible within our method allows a complete, controlled calculation on the disordered strongly interacting problem.

4 pages, 2 column revtex, 5 embedded figures

References in corpus (10)

• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• Hybrid Monte Carlo algorithm for the Double Exchange Model
• Monte Carlo Simulations for the Magnetic Phase Diagram of the Double Exchange Hamiltonian
• ``Flux'' state in double exchange model
• Ferromagnetic transition in a double-exchange system
• Ferromagnetic transition in a double-exchange system containing impurities
• Dynamical mean-field theory of a double-exchange model with diagonal disorder
• Magnetic Order in the Double Exchange Model in Infinite Dimensions
• Transition Temperature and Magnetoresistance in Double-Exchange Compounds with Moderate Disorder
• Impurity Effect on Ferromagnetic Transition in Double-Exchange Systems

Cited by in corpus (11)

• Frustration-induced insulating chiral spin state in itinerant triangular-lattice magnets
• Highly anisotropic resistivities in the double-exchange model for strained manganites
• Effects of correlated disorder on the magnetism of double exchange systems
• Disorder-Induced First Order Transition and Curie Temperature Lowering in Ferromagnatic Manganites
• Non-magnetic B-site Impurities Induce Ferromagnetic Tendencies in CE Manganites
• Instabilities and Insulator-Metal transitions in Half-Doped Manganites induced by Magnetic-Field and Doping
• Transport and Localisation in the Presence of Strong Structural and Spin Disorder
• Double Exchange Models: Self Consistent Renormalisation
• Theory of magnetism in La${}_2$NiMnO${}_6$
• Effective Ruderman-Kittel-Kasuya-Yosida-like interaction in diluted double-exchange model: self-learning Monte Carlo approach
• Inhomogeneous Phases in a Double-Exchange Magnet with Long Range Coulomb Interactions