Magnetic and transport properties of rare-earth Au and Cu amorphous alloys

Journal Article · Thu Nov 01 04:00:00 EST 1979 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.326826· OSTI ID:5894522

McGuire, T R; Gambino, R J

Magnetic moment, Hall effect and resistivity of amorphous film alloys of rare earth metals with 0.4 to 0.6 atomic fraction of Au or Cu have been studied. Alloys with Nd, Gd, Dy, Tb and Ho are ferromagnetic at 4.2 /sup 0/K. All but Gd have Curie temperatures below 20 /sup 0/K; for Gd-Au and Gd-Cu T/sub c/ is approximately 100 /sup 0/K. In addition the Gd alloys have almost full magnetization (4..pi..M) while the remaining ferromagnetic rare earth alloys have values of 4..pi..M only one-third to one-half of the expected saturation. Resistivities of the alloys range from 80 ..mu cap omega.. cm for Pr-Cu to 230 ..mu cap omega.. cm for Nd-Au and in general they have small negative temperature coefficients. The spontaneous Hall effect is positive for all the light rare earths with Au including Eu and negative for Gd and the remaining heavy rare earths. In the RE-Cu series the same is true except Dy through Tm have positive Hall values. The Hall Coefficient R/sub s/ for the heavy rare earths is largest for Gd where .R/sub s/approx. =-0.5 x 10/sup -9/..cap omega.. cm/G. The sign of the Hall effect in the Au series can be attributed in part to conduction electron interactions with the spin of the rare earth atoms since the spins point in opposite directions for the light and heavy rare earths. In addition, for the heavy rare earth-Au series the tangent of the Hall angle, rho/sub H//rho, is proportional to the paramagnetic theta value of the alloy. The positive shift of rho/sub H//rho for the RE-Cu series may have its origin in polarization of Cu by the RE moments.

• Research Organization: IBM T. J. Watson Research Center, Yorktown Heights, N. Y. 10598
• OSTI ID: 5894522
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 50:B11; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
AMORPHOUS STATE
COPPER ALLOYS
CURIE POINT
DYSPROSIUM ALLOYS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FERROMAGNETISM
FILMS
GADOLINIUM ALLOYS
GOLD ALLOYS
HALL EFFECT
HOLMIUM ALLOYS
LOW TEMPERATURE
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
MAGNETISM
MAGNETIZATION
NEODYMIUM ALLOYS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
TERBIUM ALLOYS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE