Search Patents
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Patent number: 7190853Abstract: 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: GrantFiled: June 25, 2002Date of Patent: March 13, 2007Assignee: Massachusetts Institute of TechnologyInventors: John D. Joannopoulos, Shanhui Fan, Michal Lispon, Kevin M. Chen, Lionel C. Kimerling
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Patent number: 5682401Abstract: 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: GrantFiled: June 18, 1996Date of Patent: October 28, 1997Assignee: Massachusetts Institute of TechnologyInventors: John D. Joannopoulos, Shanhui Fan, Pierre R. Villeneuve, Robert D. Meade
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Patent number: 6853789Abstract: 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: GrantFiled: June 19, 2001Date of Patent: February 8, 2005Inventors: Attila Mekis, Shanhui Fan, John D. Joannopoulos, Pierre Villeneuve
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Creating large bandwidth line defects by embedding dielectric waveguides into photonic crystal slabs
Publication number: 20040001683Abstract: 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: ApplicationFiled: November 8, 2002Publication date: January 1, 2004Applicant: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Wah Tung Lau, Shanhui Fan -
Patent number: 7155087Abstract: 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: GrantFiled: October 8, 2003Date of Patent: December 26, 2006Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Wonjoo Suh, Mehmet Fatih Yanik, Olav Solgaard, Shanhui Fan
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Patent number: 7412127Abstract: 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: GrantFiled: August 15, 2006Date of Patent: August 12, 2008Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Wonjoo Suh, Mehmet Fatih Yanik, Olav Solgaard, Shanhui Fan
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Creating large bandwidth line defects by embedding dielectric waveguides into photonic crystal slabs
Patent number: 6957003Abstract: 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: GrantFiled: November 8, 2002Date of Patent: October 18, 2005Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Wah Tung Lau, Shanhui Fan -
Patent number: 7417219Abstract: 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: GrantFiled: September 20, 2006Date of Patent: August 26, 2008Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Peter B. Catrysse, Hocheol Shin, Shanhui Fan