Understanding the insulating phase in colossal magnetoresistance manganites: shortening of the Jahn-Teller long-bond across the phase diagram of La1-xCaxMnO3

E S Bozin; M Schmidt; A J Deconinck; G Paglia; J F Mitchell; T Chatterji; P G Radaelli; Th Proffen; S J L Billinge

doi:10.1103/PhysRevLett.98.137203

Understanding the insulating phase in colossal magnetoresistance manganites: shortening of the Jahn-Teller long-bond across the phase diagram of La1-xCaxMnO3

Phys Rev Lett. 2007 Mar 30;98(13):137203. doi: 10.1103/PhysRevLett.98.137203. Epub 2007 Mar 27.

Authors

E S Bozin¹, M Schmidt, A J Deconinck, G Paglia, J F Mitchell, T Chatterji, P G Radaelli, Th Proffen, S J L Billinge

Affiliation

¹ Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-2320, USA.

PMID: 17501235
DOI: 10.1103/PhysRevLett.98.137203

Abstract

The detailed evolution of the magnitude of the local Jahn-Teller (JT) distortion in La(1-x)Ca(x)MnO3 is obtained across the phase diagram for 0< or =x< or =0.5 from high-quality neutron diffraction data using the atomic pair distribution function method. A local JT distortion is observed in the insulating phase for all Ca concentrations studied. However, in contrast with earlier local structure studies, its magnitude is not constant, but decreases continuously with increasing Ca content. This observation is at odds with a simple small-polaron picture for the insulating state.