Issue
EPL
Volume 86, Number 2, April 2009
Article Number 27003
Number of page(s) 5
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
DOI http://dx.doi.org/10.1209/0295-5075/86/27003
Published online 04 May 2009
EPL, 86 (2009) 27003
DOI: 10.1209/0295-5075/86/27003

Conductance switching and inhomogeneous field melting in the charge ordered manganites

Anamitra Mukherjee, Kalpataru Pradhan and Pinaki Majumdar

Harish-Chandra Research Institute - Chhatnag Road, Jhusi, Allahabad 211019, India

anam@mri.ernet.in

received 12 November 2008; accepted in final form 18 March 2009; published April 2009
published online 4 May 2009

Abstract
The field-induced switching of conductance in the charge ordered half-doped manganites is controlled by the combination of metastability, an inhomogeneous high-field state, and cation disorder. We study this non-equilibrium problem via real space Monte Carlo on a disordered strong coupling model appropriate to the manganites. We reproduce the variation of the switching fields with the mean ionic radius rA and cation disorder $\sigma _{A}$, and demonstrate how the experimental features arise from the proximity of several phases in the Landau free-energy landscape. Our prediction for the field melted state is consistent with a growing body of experimental evidence.

PACS
75.47.Lx - Manganites.
71.27.+a - Strongly correlated electron systems; heavy fermions.
75.30.Kz - Magnetic phase boundaries (including magnetic transitions, metamagnetism, etc.).

© EPLA 2009