Disorder-induced orbital ordering in doped manganites

Abstract

We study the effect of quenched disorder on the ordering of orbital and magnetic degrees of freedom in a two-dimensional, two-band double-exchange model for $e_g$ electrons coupled to Jahn-Teller distortions. Using a real-space Monte Carlo method, we find that disorder can induce a short-range ordering of the orbital degrees of freedom near 30% hole doping. The most striking consequence of this short range ordering is a strong increase in the low temperature resistivity. The real-space approach allows to analyze the spatial patterns of the charge, orbital, and magnetic degrees of freedom, and the correlations among them. The magnetism is inhomogeneous on the nanoscale in the short-range orbitally ordered state.

7 pages, 7 figures

References in corpus (4)

• Competing Orders and Disorder-induced Insulator to Metal Transition in Manganites
• Insulator to Metal Transition Induced by Disorder in a Model for Manganites
• Monte Carlo Study of Doping Change and Disorder Effect on Double Exchange Ferromagnetism
• The Truncated Polynomial Expansion Monte Carlo Method for Fermion Systems Coupled to Classical Fields: A Model Independent Implementation