Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem

E. I. Rashba

doi:10.1103/physrevb.62.r16267

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Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem

E. I. Rashba

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Abstract

Theory of electrical spin injection from a ferromagnetic (FM) metal into a normal (N) conductor is presented. We show that tunnel contacts (T) can dramatically increase spin injection and solve the problem of the mismatch in the conductivities of a FM metal and a semiconductor microstructure. We also present explicit expressions for the spin-valve resistance of FM-T-N- and FM-T-N-T-FM-junctions with tunnel contacts at the interfaces and show that the resistance includes both positive and negative contributions (Kapitza resistance and injection conductivity, respectively).

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E. I. Rashba. 2000-10-30. Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem. https://doi.org/10.1103/physrevb.62.r16267

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