Bias dependent features in spin transport as a probe of the conduction band minima in Si

摘要

Unusual features in the bias dependence of spin transport are observed in aCo/Au/NiFe spin valve fabricated on a highly textured Cu(100)/Si(100) Schottkyinterface, exploiting the local probing capabilities of a Ballistic electronmagnetic microscope (BEMM). This arises due to local differences in the strainand the presence of misfit dislocations at the Schottky interface that enhancesspin flip scattering and broadens the energy and angular distribution of thetransmitted electrons. Cumulatively, these enable the transmitted hot electronsto probe the different conduction band minima in Si, giving rise to such biasdependent features in the magnetocurrent. This study reveals new insights intothe spin dependence of transmission in an indirect band gap semiconductor as Siand highlights the unique capabilities of BEMM in probing local differences inspin transport across such textured interfaces.