Measuring the spin polarization of a metal with a superconducting point contact
A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.
Soulen Jr RJ
R. J. Soulen Jr., M. S. Osofsky, B. Nadgorny, T. Ambrose, S. F. Cheng, P. R. Broussard, Materials Physics, Naval Research Laboratory, Washington, DC 20375, USA. J. M. Byers, Department of Physics, George Washington University, Washington, DC 2.
Byers
JM
Osofsky
MS
Nadgorny
B
Ambrose
T
Cheng
SF
Broussard C T Tanaka PR
Nowak
J
Moodera
JS
Barry
A
Coey
JMD