Abstract: The present invention uses quantum interference of one and two photon absorption from a multiple color fields to optically inject ballistic spin currents in unbiased photoconductors. The spin currents can be generated with and without an accompanying electrical current and can be controlled using the relative phase of the colors. In one aspect of the there is provided a method of generating spin currents in a photoconductor material comprising producing a first coherent light beam having a first frequency &ohgr;1 and a second coherent light beam having a frequency twice the first frequency 2&ohgr;1, polarizing the first and second coherent light beams to have a preselected polarization with respect to each other, and simultaneously irradiating a selected region of the photoconductor material with the first coherent light beam and the second coherent light beam to generate a spin current in the photoconductor.

Abstract: The present invention uses quantum interference of one and two photon absorption from a multiple color fields to optically inject ballistic spin currents in unbiased photoconductors. The spin currents can be generated with and without an accompanying electrical current and can be controlled using the relative phase of the colors. In one aspect of the there is provided a method of generating spin currents in a photoconductor material comprising producing a first coherent light beam having a first frequency &ohgr;1 and a second coherent light beam having a frequency twice the first frequency 2&ohgr;1, polarizing the first and second coherent light beams to have a preselected polarization with respect to each other, and simultaneously irradiating a selected region of the photoconductor material with the first coherent light beam and the second coherent light beam to generate a spin current in the photoconductor.

Abstract: A method and apparatus for generating and controlling the propagation of electrons in a semiconductor material using a plurality of beams of coherent light is disclosed. The direction and magnitude of propagation of the electrons in the semiconductor are controlled by varying the polarization of the coherent beams with respect to the semiconductor material, and in particular the crystallographic axis of the semiconductor material. The electrons are generated and controlled by use of three coherent beams which are related such that the frequency of one of the beams is substantially equal to the sum of the frequencies of the other beams, and the first beam produces substantially the same number of electrons in the semiconductor material that the other beams produce together. A selected region of the semiconductor material is simultaneously irradiated with all of the beams of light. The semiconductor material is at approximately room temperature.