ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
We have performed magnetic and transport measurements on a series of Nd0.67Sr0.33Mn1−xFexO3 polycrystalline compounds with x=0.0, 0.05, 0.10, and 0.15. For the Fe-undoped Nd0.67Sr0.33MnO3 (NSMO) materials, a magnetoresistance (MR) as high as ∼33% was observed at the metal–insulator transition temperature, Tp=273 K, in a magnetic field of 10 kOe. Fe substitution in Mn sites leads to a reduction in Tp and an increase in the overall MR. A 10% Fe contribution increases the MR up to about 65% and lowers Tp to 88 K. The calculated magnetic moment at 5 K and an applied field at 9 T for the parent NSMO is 4.21 μB and decreases continuously with an increasing amount of iron added. It was found that with the same amount of Fe doping, the Curie temperature, TC, decreases much faster in the Nd-based system than in the corresponding La-based system. The enhanced colossal magnetoresistance and the suppression of ferromagnetism observed in this compound can be interpreted as due to the weakening of the double exchange mechanism by Fe3+ ions, which causes the localization of the hopping electrons. © 2002 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1421044
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