Phys. Rev. B 71, 014430 (2005) [4 pages]Nuclear magnetic resonance study of insulator-metal transitions in (Pr,Ca)MnO3
C. J. Oates *, Cz. Kapusta, and M. Sikora
P. C. Riedi
C. Martin, C. Yaicle, and A. Maignan
M. R. Ibarra Received 17 April 2004; revised 3 September 2004; published 21 January 2005 An NMR study of polycrystalline Pr0.5Ca0.5Mn1−xGaxO3 ( x=0 and 0.03) and Pr0.67Ca0.33MnO3 at 3 K is presented. Zero-field spin-echo spectra of the Ga-doped compound consist of an overlapping 69,71Ga signal at 74 MHz (hyperfine field of 5.3 T) and a 55Mn double-exchange (DE) line at 375 MHz (35.5 T). Measurements in an applied field show a steplike increase in the DE line intensity, which corresponds to an increase of the amount of the ferromagnetic metallic phase. This coincides with a steplike feature in the bulk magnetization measurements. The effect is similar to that in the previous field-dependent 55Mn NMR measurements of Pr0.67Ca0.33MnO3 . The insulator - metal transition for Pr0.67Ca0.33MnO3 , at ambient pressure, occurs at fields greater than 5 T; however, at 1.1 GPa, the DE line corresponding to the ferromagnetic metallic phase is already present at zero field. ©2005 The American Physical Society
URL: http://link.aps.org/doi/10.1103/PhysRevB.71.014430 * Email address: oates@uci.agh.edu.pl [ Abstract | Previous article | Next article | Issue 1 ] |
A new free weekly publication from APS 
Read the latest from Physics:
Viewpoint: Can superconducting rings provide clues to the early development of the universe? |
About PROLA | Terms and Conditions | Subscriptions | Search | Help
Content in PROLA © 2009 by The American Physical Society All rights reserved. PROLA™ is a trademark of The American Physical Society. Use of APS online journals implies that the user has read and agrees to the Terms and Conditions in the Subscription Agreement.