Structural Origin of the Metal-Insulator Transition of Multiferroic BiFeO3 - Condensed Matter > Materials ScienceReport as inadecuate




Structural Origin of the Metal-Insulator Transition of Multiferroic BiFeO3 - Condensed Matter > Materials Science - Download this document for free, or read online. Document in PDF available to download.

Abstract: We report X-ray structural studies of the metal-insulator phase transition inbismuth ferrite, BiFeO3, both as a function of temperature and of pressure 931oC at atmospheric pressure and ca. 45 GPa at ambient temperature. Based on theexperimental results, we argue that the metallic gamma-phase is notrhombohedral but is instead the same cubic Pm3m structure whether obtained viahigh temperature or high pressure, that the MI transition is second order orvery nearly so, that this is a band-type transition due to semi-metal bandoverlap in the cubic phase and not a Mott transition, and that it is primarilystructural and not an S=5-2 to S=1-2 high-spin-low-spin electronic transition.Our data are compatible with the orthorhombic Pbnm structure for the beta-phasedetermined definitively by the neutron scattering study of Arnold et al .Phys.Rev. Lett. 2009; the details of this beta-phase had also been controversial,with a remarkable collection of five crystal classes cubic, tetragonal,orthorhombic, monoclinic, and rhombohedral! all claimed in recentpublications.



Author: S. A. T. Redfern, J. N. Walsh, S. M. Clark, G. Catalan, J. F. Scott

Source: https://arxiv.org/



DOWNLOAD PDF




Related documents