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Published on: February 1, 2017
Origin of the inverse spin switch effect in superconducting spin valves
1Department of Physics, University of California, Irvine, California 92697-4575, USA.
Physical Review Letters
|August 8, 2009
Summary
The spin switch effect (SSE) in ferromagnet/superconductor/ferromagnet spin valves shows both standard and inverse behaviors. Inverse SSE in NiFe/Nb/NiFe/IrMn valves is caused by vortex flow from magnetic domain walls.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- The spin switch effect (SSE) describes resistance differences in ferromagnet/superconductor/ferromagnet (F/S/F) spin valves near the superconducting transition temperature (Tc).
- Standard SSE (RP>RAP) and inverse SSE (RP
Purpose of the Study:
- To investigate the coexistence of standard and inverse SSE in Ni81Fe19/Nb/Ni81Fe19/Ir25Mn75 spin valves.
- To elucidate the physical mechanism behind the observed inverse SSE.
Main Methods:
- Fabrication of NiFe/Nb/NiFe/IrMn spin valve heterostructures.
- Electrical resistance measurements as a function of temperature and magnetic field.
- Analysis of magnetic domain structures and stray fields.
Main Results:
- Observed coexistence of both standard (RP>RAP) and inverse (RP
- Demonstrated that the inverse SSE originates from the dissipative flow of superconducting vortices.
- Identified stray magnetic fields from Néel domain-wall pairs in the ferromagnet layers as the driving force for vortex motion.
Conclusions:
- The study reveals a novel mechanism for inverse SSE in F/S/F spin valves.
- Understanding this phenomenon is crucial for developing advanced spintronic devices.
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