Correlations Between the Magnetic and Structural Properties of Ca Doped BiMnO3

Published

April 1, 2001

Author(s)

H Woo, T A. Tyson, Mark Croft, S W. Cheong, Joseph Woicik

Abstract

Bi1-xCaxMnO3 (BCMO) is known to exhibit charge ordering for a much broader range of x than the classicLa1-xCaxMnO3 (LCMO) system. However, the properties of BCMO over the entire doping range are not well understood. We have performed magnetization and resistivity measurements as well as x-ray absorption and x-ray diffraction (XRD) measurements, on BCMO to correlate transport, structural and magnetic properties. The BCMO system is insulating and antiferromagnetic (AF) for the entire range of x studied (x > 0.4) except near x 0.9 where we find a canted spin arrangement with approximately one Bohr magneton per Mn site. Detailed magnetization measurement was performed as a function of field and temperature to explore the net moment on the Mn sites as a function of x and reveal the charge ordering and N el temperatures. X-ray absorption measurements reveal significant structural distortion in the Mn-O bond distributions with increasing Bi content which correlates directly with increasing charge ordering temperatures. Moreover, the x-ray diffraction data reveal splittings consistent with lower symmetry cells as Bi content increases. These structural-magnetic correlations point to the importance of Mn-O distortions in stabilizing the charge ordered state in the manganites.

Citation

Physical Review B (Condensed Matter and Materials Physics)

Volume

63

Issue

No. 13

Pub Type

Journals

Keywords

antiferromagnetic, Bi_1-xCa_xMnO₃(BCMO), La_1-xCa_xMnO₃(LCMO), x-ray diffraction (XRD)

Citation

Woo, H. , Tyson, T. , Croft, M. , Cheong, S. and Woicik, J. (2001), Correlations Between the Magnetic and Structural Properties of Ca Doped BiMnO₃, Physical Review B (Condensed Matter and Materials Physics) (Accessed December 15, 2024)