Electrical spin injection and detection in lateral all-semiconductor   devices
  Electrical injection and detection of spin-polarized electrons is demonstrated for the first time in a single wafer, all-semiconductor, GaAs-based lateral spintronic device, employing p+-(Ga,Mn)As/n+-GaAs ferromagnetic Esaki diodes as spin aligning contacts. The conversion of spin-polarized holes into spin-polarized electrons via Esaki tunnelling leaves its mark in a bias dependence of the spin-injection efficiency, which at maximum reaches the relatively high value of 50%. 
Mariusz Ciorga, Andreas Einwanger, Ursula Wurstbauer, Dieter Schuh,   Werner Wegscheider, and Dieter Weiss