Title :
Anisotropic paramagnetic susceptibility of crystalline ruby at cryogenic temperatures
Author :
Hartnett, John G. ; le Floch, Jean-Michel ; Tobar, Michael E. ; Krupka, Jerzy ; Bourgeois, Pierre-Yves
Author_Institution :
Western Australia Univ., Crawley
fDate :
May 29 2007-June 1 2007
Abstract :
The static paramagnetic susceptibility of chromium ions in sapphire (Cr3+ in Al2O3) in zero applied static magnetic field has been determined between 4.2 K and 100 K using the whispering gallery mode technique at microwave frequencies. Although sapphire exhibits a uniaxial anisotropy in permittivity, in contrast the magnetic susceptibility has been measured to only have a susceptibility component perpendicular to the crystal axis. This component showed a strong Curie law dependence below 30 K.
Keywords :
magnetic susceptibility; paramagnetic materials; ruby; whispering gallery modes; Al2O3:Cr; Curie law; anisotropic paramagnetic susceptibility; chromium ions; cryogenic temperatures; crystalline ruby; magnetic susceptibility; microwave frequencies; static magnetic field; temperature 4.2 K to 100 K; whispering gallery mode technique; Anisotropic magnetoresistance; Chromium; Cryogenics; Crystallization; Magnetic field measurement; Magnetic susceptibility; Microwave frequencies; Paramagnetic materials; Temperature; Whispering gallery modes;
Conference_Titel :
Frequency Control Symposium, 2007 Joint with the 21st European Frequency and Time Forum. IEEE International
Conference_Location :
Geneva
Print_ISBN :
978-1-4244-0646-3
Electronic_ISBN :
1075-6787
DOI :
10.1109/FREQ.2007.4319158
