Probing Ferromagnets with Andreev Reflection
نویسندگان
چکیده
High transmissivity, ferromagnet-superconductor thin film nanocontacts are studied experimentally. Compared to nonmagnetic metal-superconductor contacts, Andreev reflection is strongly suppressed due to the spin polarization of conduction electrons in the ferromagnet. This effect is used to measure both the transparency of the interface and spin polarization of the direct current in the ferromagnet in contrast to the spin polarization of the tunneling current previously measured in ferromagnet-insulatorsuperconductor systems. [S0031-9007(98)07318-9]
منابع مشابه
Andreev reflection through a quantum dot coupled with two ferromagnets and a superconductor
We study the Andreev reflection (AR) in a three terminal mesoscopic hybrid system, in which two ferromagnets (F1 and F2) are coupled to a superconductor (S) through a quantum dot (QD). By using non-equilibrium Green function, we derive a general current formula which allows arbitrary spin polarizations, magnetization orientations and bias voltages in F1 and F2. The formula is applied to study b...
متن کاملProbing spin polarization with Andreev reflection: A theoretical basis
Andreev reflection at the interface between a ferromagnet and a superconductor has become a foundation of a versatile technique of measuring the spin polarization of magnetic materials. In this article we will briefly outline a general theory of Andreev reflection for spin-polarized systems and arbitrary Fermi surface in two limiting cases of ballistic and diffusive transport. © 2001 American I...
متن کاملMagnetoanisotropic Andreev reflection in ferromagnet-superconductor junctions.
Andreev reflection spectroscopy of ferromagnet-superconductor (FS) junctions [corrected] is an important probe of spin polarization. We theoretically investigate spin-polarized transport in FS junctions in the presence of Rashba and Dresselhaus interfacial spin-orbit fields and show that Andreev reflection can be controlled by changing the magnetization orientation. We predict a giant in- and o...
متن کاملTransport spin polarisation in SrRuO3 measured through Point Contact Andreev reflection
We report a study in which Andreev reflection using a Nb point contact is used to measure the transport spin polarisation of the 4d itinerant ferromagnet SrRuO3. By performing the study in high quality thin films with residual resistivities less than 7μΩ-cm, we ensure that the study is done in the ballistic limit, a regime which is difficult to reach in oxide ferromagnets. The degree of transpo...
متن کاملar X iv : c on d - m at / 9 41 00 14 v 1 6 O ct 1 99 4 Andreev reflection in ferromagnet – superconductor junctions
The transport properties of a ferromagnet–superconductor (FS) junction are studied in a scattering formulation. Andreev reflection at the FS interface is strongly affected by the exchange interaction in the ferromagnet. The conductance GFS of a ballistic point contact between F and S can be both larger or smaller than the value GFN with the superconductor in the normal state, depending on the r...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1998