Interaction of Mu with spin current in GaAs/GaAsP/Si

We propose a mechanism for probing the polarized electron flow (spin curren t) by using the spin dependence of the exchange scattering of conduction el ectrons at Muonium (Mu) and/or muon (mu(+)) center resulting from the Pauli exclusion principle. In order to study the feasibility of such a mechanism , we performed the MuSR experiment in Si covered by a strained GaAs overlay er in the presence of photo-induced polarized electrons. The MuSR pattern s hows a significant dependence on the wavelength of the laser light. A sligh t difference in the triplet-singlet population of Mu depending on the polar ization direction of the spin current is also observed at the resonance wav elength of the strained GaAs layer. These results suggest the existence of spin-dependent electron scattering at the Mu center. (C) 2000 Elsevier Scie nce B.V. All rights reserved.