Eur. Phys. J. B (2014) 87: 238
https://doi.org/10.1140/epjb/e2014-50232-0

Regular Article

A real space description of magnetic field induced melting in the charge ordered manganites: I. The clean limit

¹ Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
² Harish-Chandra Research Institute, Chhatnag Road, Jhusi, 211019 Allahabad, India

^a e-mail: amukher5@utk.edu

Received: 7 April 2014
Received in final form: 10 August 2014
Published online: 20 October 2014

Abstract

We study the melting of charge order in the half doped manganites using a model that incorporates double exchange, antiferromagnetic superexchange, and Jahn-Teller coupling between electrons and phonons. We primarily use a real space Monte Carlo technique to study the phase diagram in terms of applied field (h) and temperature (T), exploring the melting of charge order with increasing h and its recovery on decreasing h. We observe hysteresis in this response, and discover that the “field melted” high conductance state can be spatially inhomogeneous even without extrinsic disorder. The hysteretic response plays out in the background of field driven equilibrium phase separation. Our results, exploring h, T, and the electronic parameter space, are backed up by analysis of simpler limiting cases and a Landau framework for the field response. This paper focuses on our results in the “clean” systems, a companion paper studies the effect of cation disorder on the melting phenomena.