The magnetoresistance of two terminal lateral semiconductor spin valves with respect to varying mesa size is studied. It is shown theoretically that extended regions outside the spin-current path can act as an additional source of spin-relaxation, decreasing the magnetoresistance response. From a simplified expression of magnetoresistance derived from spin-diffusion equations, we show that it is important to etch away these extended regions for devices with channel lengths much smaller than the spin-diffusion length in order to achieve maximum magnetoresistance. Preliminary experimental data on a two terminal local spin valve are in good agreement with the theory established in this article.
Bibliographical noteFunding Information:
The work is being supported by the Office of Naval Research under Grant No. N00014-09-1-0086. S.S. acknowledges funding from the Institute for Nanoelectronics Discovery and Exploration.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)