Document Type
Journal Article
RIS ID
20074
Abstract
The authors present their studies on the band structures and on the magnetic and magnetotransport properties of the high pressure phase of Sr2-xRExCoO4 [rare earth (RE)=Gd and Y, x=0.1-0.5] compounds which were synthesized by a high pressure and high temperature technique. The authors found that as x increases, the magnetoresistance {(PH-P0)/p0} increases up to -17% at 5 K and 7 T, which is 2.5 times higher than that for undoped Sr2CoO4, although the ferromagnetic transition drops from 255 to 200 K for the Gd doping with x=0.3. The saturation moments at low temperature are significantly enhanced for the Gd doped Sr2CoO4. Observation of a close correlation between resistance and field revealed a strong spin-dependent tunneling magnetoresistance. First-principles band structure calculations indicate that high spin polarization is present for both undoped and doped compounds.
Publication Details
Wang, X, Takayama-Muromachi, E, Dou, SX & Cheng, Z (2007), Band structures, magnetic properties, and enhanced magnetoresistance in the high pressure phase of Gd and Y doped two-dimensional perovskite Sr2CoO4 compounds, Applied Physics Letters, 91(6), pp. 062501-1-062501-3.