High-field magnetoresistance of Fe/GaAs/Fe tunnel junctions
arXiv:cond-mat/0404351 · doi:10.1063/1.1774255
Abstract
We investigate transport through 6 to 10 nm thin epitaxial GaAs(001) barriers sandwiched between polycrystalline iron films. Apart from a pronounced tunneling magnetoresistance effect (TMR) at low magnetic fields we observe a distinct negative magnetoresistance (MR) at low and a positive MR at higher temperatures. We show that the negative MR contribution is only observed for the ferromagnetic iron contacts but is absent if iron is replaced by copper or gold electrodes. Possible explanations of the negative MR involve suppression of spin-flip scattering or Zeeman splitting of the tunneling barrier.
arXiv comment12 pages, 4 figures, submitted to Appl. Phys. Lett
References in corpus (4)
- Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor
- Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem
- Efficient Electrical Spin Injection from a Magnetic Metal / Tunnel Barrier Contact into a Semiconductor
- Analysis of the Transport Process Providing Spin Injection through an Fe/AlGaAs Schottky Barrier
Cited by in corpus (5)
- Semiconductor Spintronics
- Bias dependent inversion of tunneling magnetoresistance in Fe/GaAs/Fe tunnel junctions
- All-electrical measurement of spin injection in a magnetic - junction diode
- Spin-polarized tunneling through randomly transparent magnetic junctions: Reentrant magnetoresistance approaching the Julliere limit
- Nonmonotonic inelastic tunneling spectra due to surface spin excitations in ferromagnetic junctions