Patents by Inventor Ravi D. R. Bhat

Ravi D. R. Bhat has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method and apparatus for generating and controlling spin propagation using one or more coherent light beams
    Patent number: 6643047
    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.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: November 4, 2003
    Inventors: Ravi D. R. Bhat, John Edward Sipe, Henry Martin Van Driel
  • Method and apparatus for generating and controlling spin propagation using one or more coherent light beams
    Publication number: 20020135852
    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.
    Type: Application
    Filed: March 22, 2002
    Publication date: September 26, 2002
    Inventors: Ravi D.R. Bhat, John Edward Sipe, Henry Martin Van Driel