Search Patents
  • Patent number: 7190853
    Abstract: A system for dispersion compensation is provided including a plurality of optical cavities with each including a specific resonant frequency and resonant linewidth. At least one coupling element interconnects the optical cavities. The at least one coupling element defines the coupling strength between the cavities. The optical cavities are interconnected with the at least one coupled element that forms a multi-cavity structure. The multi-cavity structure generates appropriate dispersion properties for dispersion compensation purposes.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: March 13, 2007
    Assignee: Massachusetts Institute of Technology
    Inventors: John D. Joannopoulos, Shanhui Fan, Michal Lispon, Kevin M. Chen, Lionel C. Kimerling
  • Patent number: 5682401
    Abstract: The present invention provides a resonant microcavity which includes a periodic dielectric waveguide, and a local defect in the periodic dielectric waveguide which accommodates spacial confinement of radiation generated within the waveguide around the defect. In an alternative embodiment, the present invention provides a method of enhancing radiation confinement within a resonant microcavity and minimizing radiation losses into an associated substrate, the microcavity configured within a periodic dielectric waveguide as a local defect which exhibits spacial radiation confinement, the method including the step of increasing the refractive index contrast between the microcavity and the substrate.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: October 28, 1997
    Assignee: Massachusetts Institute of Technology
    Inventors: John D. Joannopoulos, Shanhui Fan, Pierre R. Villeneuve, Robert D. Meade
  • Patent number: 6853789
    Abstract: A method of making a low-loss electromagnetic wave resonator structure. The method includes providing a resonator structure, the resonator structure including a confining device and a surrounding medium. The resonator structure supporting at least one resonant mode, the resonant mode displaying a near-field pattern in the vicinity of said confining device and a far-field radiation pattern away from the confining device. The surrounding medium supports at least one radiation channel into which the resonant mode can couple. The resonator structure is specifically configured to reduce or eliminate radiation loss from said resonant mode into at least one of the radiation channels, while keeping the characteristics of the near-field pattern substantially unchanged.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: February 8, 2005
    Inventors: Attila Mekis, Shanhui Fan, John D. Joannopoulos, Pierre Villeneuve
  • Publication number: 20040001683
    Abstract: We introduce a general designing procedure that allows us, for any given photonic crystal slab, to create an appropriate line defect structure that possesses single-mode bands with large bandwidth and low dispersion within the photonic band gap region below the light line. This procedure involves designing a high index dielectric waveguide that is phase matched with the gap of the photonic crystal slab, and embedding the dielectric waveguide as a line defect into a crystal in a specific configuration that is free of edge states within the guiding bandwidth. As an example, we show a single mode line defect waveguide with a bandwidth approaching 13% of the center-band frequency, and with a linear dispersion relation throughout most of the bandwidth.
    Type: Application
    Filed: November 8, 2002
    Publication date: January 1, 2004
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Wah Tung Lau, Shanhui Fan
  • Patent number: 7155087
    Abstract: We introduce a mechanically tunable photonic crystal structure consisting of coupled photonic crystal slabs. Using both analytic theory, and first-principles finite-difference time-domain simulations, we demonstrate that the transmission and reflection coefficients for light normally incident upon such structures can be highly sensitive to nano-scale variations in the spacing between the slabs. Moreover, by specifically configuring the photonic crystal structures, the high sensitivity can be preserved in spite of significant fabrication-related disorders. We expect such a structure to play important roles in micro-mechanically tunable optical sensors and filters.
    Type: Grant
    Filed: October 8, 2003
    Date of Patent: December 26, 2006
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Wonjoo Suh, Mehmet Fatih Yanik, Olav Solgaard, Shanhui Fan
  • Patent number: 7412127
    Abstract: We introduce a mechanically tunable photonic crystal structure consisting of coupled photonic crystal slabs. Using both analytic theory, and first-principles finite-difference time-domain simulations, we demonstrate that the transmission and reflection coefficients for light normally incident upon such structures can be highly sensitive to nano-scale variations in the spacing between the slabs. Moreover, by specifically configuring the photonic crystal structures, the high sensitivity can be preserved in spite of significant fabrication-related disorders. We expect such a structure to play important roles in micro-mechanically tunable optical sensors and filters.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: August 12, 2008
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Wonjoo Suh, Mehmet Fatih Yanik, Olav Solgaard, Shanhui Fan
  • Patent number: 6957003
    Abstract: We introduce a general designing procedure that allows us, for any given photonic crystal slab, to create an appropriate line defect structure that possesses single-mode bands with large bandwidth and low dispersion within the photonic band gap region below the light line. This procedure involves designing a high index dielectric waveguide that is phase matched with the gap of the photonic crystal slab, and embedding the dielectric waveguide as a line defect into a crystal in a specific configuration that is free of edge states within the guiding bandwidth. As an example, we show a single mode line defect waveguide with a bandwidth approaching 13% of the center-band frequency, and with a linear dispersion relation throughout most of the bandwidth.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: October 18, 2005
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Wah Tung Lau, Shanhui Fan
  • Patent number: 7417219
    Abstract: Using a realistic plasmonic model, an optically thick electrically conductive film with subwavelength hole or holes therein is shown to always support propagating modes near the surface plasmon frequency, where cross-sectional dimensions of the hole or holes are less than about ?/2nh, ? being the wavelength of the light and nh the refractive index of the dielectric material in the hole or holes. This is the case even when material losses are taken into account. Based on the dispersion analysis, in both a single hole or hole array designs, propagating modes play a dominant role in the transport properties of incident light. These structures exhibit a new region of operation, while featuring a high packing density and diffraction-less behavior.
    Type: Grant
    Filed: September 20, 2006
    Date of Patent: August 26, 2008
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Peter B. Catrysse, Hocheol Shin, Shanhui Fan