Patents by Inventor Henry M. van Driel

Henry M. van Driel 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 of varying optical properties of photonic crystals on fast time scales using energy pulses
    Patent number: 6870970
    Abstract: The present invention provides a method for fast switching of optical properties in photonic crystals using pulsed/modulated free-carrier injection. The results disclosed herein indicate that several types of photonic crystal devices can be designed in which free carriers are used to vary dispersion curves, stop gaps in materials with photonic bandgaps to vary the bandgaps, reflection, transmission, absorption, gain, or phase. The use of pulsed free carrier injection to control the properties of photonic crystals on fast timescales forms the basis for all-optical switching using photonic crystals. Ultrafast switching of the band edge of a two-dimensional silicon photonic crystal is demonstrated near a wavelength of 1.9 ?m. Changes in the refractive index are optically induced by injecting free carriers with 800 nm, 300 fs pulses. Band-edge shifts have been induced in silicon photonic crystals of up to 29 nm that occurs on the time-scale of the pump pulse.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: March 22, 2005
    Inventors: Stephen W. Leonard, Henry M. van Driel, Jorg Schilling, Ralf Boris Wehrspohn, Ulrich Gosele, Stefan Senz
  • Method of varying optical properties of photonic crystals on fast time scales using energy pulses
    Publication number: 20030202728
    Abstract: The present invention provides a method for fast switching of optical properties in photonic crystals using pulsed/modulated free-carrier injection. The results disclosed herein indicate that several types of photonic crystal devices can be designed in which free carriers are used to vary dispersion curves, stop gaps in materials with photonic bandgaps to vary the bandgaps, reflection, transmission, absorption, gain, or phase. The use of pulsed free carrier injection to control the properties of photonic crystals on fast timescales forms the basis for all-optical switching using photonic crystals. Ultrafast switching of the band edge of a two-dimensional silicon photonic crystal is demonstrated near a wavelength of 1.9 &mgr;m. Changes in the refractive index are optically induced by injecting free carriers with 800 nm, 300 fs pulses. Band-edge shifts have been induced in silicon photonic crystals of up to 29 nm that occurs on the time-scale of the pump pulse.
    Type: Application
    Filed: April 24, 2002
    Publication date: October 30, 2003
    Inventors: Stephen W. Leonard, Henry M. van Driel, Jorg Schilling, Ralf Boris Wehrspohn, Ulrich Gosele, Stefan Senz
  • Laser mode-coupling via a pulsed modulator
    Patent number: 5014277
    Abstract: A laser system wherein a pulsed switching signal is applied to the modulator to provide a mode-coupled output beam having spaced short pulses. The synchronized pulsed switching signal can be provided by an external driver and or by feedback from the laser beam.
    Type: Grant
    Filed: June 5, 1989
    Date of Patent: May 7, 1991
    Inventors: Henry M. Van Driel, Giampiero Giuliani