Title :
Intergrain magnetoresistance in electron-doped Sr2FeMoO6
Author :
Venkatesan, M. ; Fitzgerald, C.B. ; Varadaraju, U.V. ; Coey, J.M.D.
Author_Institution :
Dept. of Phys., Trinity Coll., Dublin, Ireland
fDate :
9/1/2002 12:00:00 AM
Abstract :
Electron-doped double perovskite compounds (Sr2-xLax)FeMoO6 (x=0.0, 0.5, 0.7) were synthesized by combustion synthesis using oxalic acid dihydrazide as fuel. There is an increase in Curie temperature (TC) with La substitution up to a value of 172°C for (Sr1.3La0.7)FeMoO6. The compound (Sr1.5La0.5)FeMoO6 with increased TC compared to the undoped sample, exhibits a intergrain magnetoresistance of about 3% in a field of 0.1 T. The presence of magnetoresistance in La-doped samples prepared by combustion synthesis is due to the increased number of intergrain tunnel barriers.
Keywords :
Curie temperature; ceramics; combustion synthesis; ferromagnetic materials; grain size; iron compounds; magnetoresistance; powder technology; strontium compounds; tunnelling; (SrLa)2FeMoO6; 0.1 T; Curie temperature; Sr2FeMoO6; antiferromagnetic exchange coupling; antisite defects; combustion synthesis; electron-doped double perovskite; ferromagnetic coupling; grain size; half-metallic double perovskite; high field magnetoresistance; intergrain magnetoresistance; intergrain tunnel barriers; lanthanum substitution effect; magnetoresistive sensor; oxalic acid dihydrazide fuel; pressed powder; Ceramics; Combustion; Crystallization; Fuels; Magnetic materials; Magnetoresistance; Powders; Solid state circuits; Strontium; Temperature sensors;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2002.803138
