Title :
Cryogenic magnetic properties of iron garnets diluted with Al-In and Ca-V-In combinations
Author :
Dionne, Gerald F. ; Oates, Daniel E. ; Anderson, Alfredo C. ; Hill, Michael D. ; Hokanson, Elwood L. ; Cruickshank, David B.
Author_Institution :
Lincoln Lab., MIT, Lexington, MA, USA
fDate :
7/1/2001 12:00:00 AM
Abstract :
Investigations of magnetic dilution in Y3Fe5O12 (YIG) indicate that magnetic and dielectric parameters suitable for microwave applications can be obtained at cryogenic temperatures. For simultaneous dilutions of 35% into the octahedral (a) sublattice and 27% into the tetrahedral (d) sublattice, there were no apparent degrading effects on the dielectric loss tangents. At low temperatures, a-site substitutions of In caused the expected large increases in saturation magnetization and corresponding decreases in Curie temperatures. Moreover, measurements of hysteresis loops showed that coercive fields ~0.5 Oe could be obtained at T<77 K despite the likely sharp rise in anisotropy. Dilution by In also lowered anisotropy fields by a factor greater than five from that of Y3(Fe,Al)5O12 in both {Y,Ca}3 (Fe,V,In)5O12 and Y3(Fe,Al,In) 5O12 compounds
Keywords :
Curie temperature; coercive force; dielectric losses; dilute magnetic materials; garnets; magnetic anisotropy; magnetic hysteresis; magnetisation; yttrium compounds; (Y,Ca)3(Fe,V,In)5O12; (YCa)3(FeVIn)5O12; Curie temperature; Y3(Fe,Al,In)5O12; Y3(FeAlIn)5O12; anisotropy field; chemical substitution; coercive field; cryogenic magnetic properties; dielectric loss tangent; hysteresis loop; magnetic dilution; microwave parameters; saturation magnetization; yttrium iron garnet; Anisotropic magnetoresistance; Cryogenics; Dielectric losses; Garnets; Iron; Magnetic anisotropy; Magnetic properties; Perpendicular magnetic anisotropy; Saturation magnetization; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
