Patents by Inventor Alexandre M. Bratkovski

Alexandre M. Bratkovski 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).

  • Publication number: 20090015838
    Abstract: A structure includes a film having a plurality of nanoapertures. The nanoapertures are configured to allow the transmission of a predetermined subwavelength of light through the film via the plurality of nanoapertures. The structure also includes a semiconductor layer in connection with the film to facilitate the detection of the predetermined subwavelength of light transmitted through the film.
    Type: Application
    Filed: April 26, 2007
    Publication date: January 15, 2009
    Inventors: Shih-Yuan Wang, Alexandre M. Bratkovski
  • Patent number: 7477809
    Abstract: A photonic guiding device and methods of making and using are disclosed. The photonic guiding device comprises a large core hollow waveguide configured to interconnect electronic circuitry on a circuit board. A reflective coating covers an interior of the hollow waveguide to provide a high reflectivity to enable light to be reflected from a surface of the reflective coating. A collimator is configured to collimate multi-mode coherent light directed into the hollow waveguide.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: January 13, 2009
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael Renne Ty Tan, Alexandre M. Bratkovski, Shih-Yuan (SY) Wang
  • Patent number: 7474810
    Abstract: Apparatuses and methods for modulating electromagnetic radiation are disclosed. A plasmon waveguide including an array of metallic nanoparticles disposed on a dielectric substrate is provided. The plasmon waveguide is disposed on a MEMS structure. An electromagnetic radiation signal is applied to a tapered fiber disposed proximate the MEMS structure. The intensity of the electromagnetic radiation signal passing through the tapered fiber is modified by displacing a deformable member of the MEMS structure to modify a distance between the plasmon waveguide and the tapered fiber such that an evanescent field of the tapered fiber causes a plasmon resonance in the plasmon waveguide.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: January 6, 2009
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Shih-Yuan Wang
  • Publication number: 20090001498
    Abstract: Nanowire-based photodiodes are disclosed. The photodiodes include a first optical waveguide having a tapered first end, a second optical waveguide having a tapered second end, and at least one nanowire comprising at least one semiconductor material connecting the first and second ends in a bridging configuration. Methods of making the photodiodes are also disclosed.
    Type: Application
    Filed: June 26, 2007
    Publication date: January 1, 2009
    Inventors: Shih-Yuan Wang, Michael Renne Ty Tan, Alexandre M. Bratkovski, R. Stanley Williams, Nobuhiko Kobayashi
  • Publication number: 20080310790
    Abstract: Various embodiments of the present invention are directed to nanowire-based photodetectors that can be used to convert information encoded in a channel of electromagnetic radiation into a photocurrent encoding the same information. In one embodiment of the present invention, a photodetector comprises a waveguide configured to transmit one or more channels of electromagnetic radiation. The photodetector includes a first terminal and a second terminal. The first terminal and the second terminal are positioned on opposite sides of the waveguide. The photodetector also includes a number of nanowires. Each nanowire interconnects the first terminal to the second terminal and a portion of each nanowire is embedded in the waveguide.
    Type: Application
    Filed: January 29, 2007
    Publication date: December 18, 2008
    Inventors: Wei Wu, Scott Corzine, Alexandre M. Bratkovski, Shih-Yuan Wang
  • Publication number: 20080285917
    Abstract: Apparatuses and methods for modulating electromagnetic radiation are disclosed. A plasmon waveguide including an array of metallic nanoparticles disposed on a dielectric substrate is provided. The plasmon waveguide is disposed on a MEMS structure. An electromagnetic radiation signal is applied to a tapered fiber disposed proximate the MEMS structure. The intensity of the electromagnetic radiation signal passing through the tapered fiber is modified by displacing a deformable member of the MEMS structure to modify a distance between the plasmon waveguide and the tapered fiber such that an evanescent field of the tapered fiber causes a plasmon resonance in the plasmon waveguide.
    Type: Application
    Filed: May 15, 2007
    Publication date: November 20, 2008
    Inventors: Alexandre M. Bratkovski, Shih-Yuan Wang
  • Publication number: 20080266556
    Abstract: Various aspects of the present invention are directed to a nanowire configured to couple electromagnetic radiation to a selected guided wave and devices incorporating such nanowires. In one aspect of the present invention, a nanowire structure includes a substrate and at least one nanowire attached to the substrate. A diameter, composition, or both may vary generally periodically along a length of the at least one nanowire. A coating may cover at least part of a circumferential surface of the at least one nanowire. The nanowire structure may be incorporated in a device including at least one optical-to-electrical converter operable to convert a guided wave propagating along the length of the at least one nanowire, at least in part responsive to irradiation, to an electrical signal. Other aspects of the present invention are directed to methods of fabricating nanowires structured to support guided waves.
    Type: Application
    Filed: April 25, 2007
    Publication date: October 30, 2008
    Inventors: Theodore I. Kamins, Alexandre M. Bratkovski
  • Publication number: 20080266640
    Abstract: A structure includes a film having a plurality of nanoapertures and a semiconductor layer in connection with the film. The nanoapertures are configured to allow the transmission of a predetermined subwavelength of light through the film via the plurality of nanoapertures. The semiconductor layer facilitates the modulation of the predetermined subwavelength of light transmitted through the film.
    Type: Application
    Filed: April 26, 2007
    Publication date: October 30, 2008
    Inventors: Shih-Yuan Wang, Alexandre M. Bratkovski
  • Publication number: 20080264185
    Abstract: A sensing device includes a nanowire configured to deform upon exposure to a force, and a transducer for converting the deformation into a measurement. The nanowire has two opposed ends; and the transducer is operatively connected to one of the two opposed ends of the nanowire. The other of the two opposed ends of the nanowire is freestanding.
    Type: Application
    Filed: April 25, 2007
    Publication date: October 30, 2008
    Inventors: Nobuhiko P. Kobayashi, Shih-Yuan Wang, Alexandre M. Bratkovski, R. Stanley Williams
  • Publication number: 20080258079
    Abstract: Various aspects of the present invention are directed to apparatuses and methods for up-converting electromagnetic radiation. In one aspect of the present invention, a plasmonic up-converter apparatus includes an excitation source operable to emit electromagnetic radiation at an excitation frequency and at least one array of nanofeatures. The at least one array of nanofeatures is configured to produce an emission spectrum responsive to irradiation by the electromagnetic radiation. The emission spectrum has an intensity at a second harmonic frequency or a third harmonic frequency approximately equal to an intensity at a fundamental harmonic frequency, with the fundamental harmonic frequency being approximately equal to the excitation frequency.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 23, 2008
    Inventor: Alexandre M. Bratkovski
  • Publication number: 20080259981
    Abstract: Various aspects of the present invention are directed to photonic devices, such as electro-optic modulators, passive filters, and tunable filters. In one aspect of the present invention, a photonic device includes a semiconductor structure having a p-region and an n-region. A doped region is formed on or within the semiconductor structure. The doped region includes at least one generally periodic array of recesses, with the at least one generally periodic array configured to transmit electromagnetic radiation at a selected dominant wavelength. The selected dominant wavelength is tunable by varying the refractive index of the semiconductor structure.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 23, 2008
    Inventors: Shih-Yuan Wang, Alexandre M. Bratkovski
  • Publication number: 20080239462
    Abstract: An apparatus for controlling propagation of incident electromagnetic radiation is described, comprising a composite material having electromagnetically reactive cells of small dimension relative to a wavelength of the incident electromagnetic radiation. At least one of a capacitive and inductive property of at least one of the electromagnetically reactive cells is temporally controllable to allow temporal control of an associated effective refractive index encountered by the incident electromagnetic radiation while propagating through the composite material.
    Type: Application
    Filed: June 4, 2008
    Publication date: October 2, 2008
    Inventors: Philip J. Kuekes, Shih-Yuan Wang, Raymond G. Beausoleil, Alexandre M. Bratkovski, Wei Wu, M. Saif Islam
  • Publication number: 20080219311
    Abstract: Various aspects of the present invention are directed to optical structures including selectively positioned color centers, methods of fabricating such optical structures, and photonic chips that utilize such optical structures. In one aspect of the present invention, an optical structure includes an optical medium having a number of strain-localization regions. A number of color centers are distributed within the optical medium in a generally selected pattern, with at least a portion of the strain-localization regions including one or more of the color centers. In another aspect of the present invention, a method of positioning color centers in an optical medium is disclosed. In the method, a number of strain-localization regions are generated in the optical medium. The optical medium is annealed to promote diffusion of at least a portion of the color centers to the strain-localization regions.
    Type: Application
    Filed: March 8, 2007
    Publication date: September 11, 2008
    Inventors: Alexandre M. Bratkovski, Theodore I. Kamins
  • Publication number: 20080218740
    Abstract: Embodiments of the present invention are related to nanowire-based devices that can be configured and operated as modulators, chemical sensors, and light-detection devices. In one aspect, a nanowire-based device includes a reflective member, a resonant cavity surrounded by at least a portion of the reflective member, and at least one nanowire disposed within the resonant cavity. The nanowire includes at least one active segment selectively disposed along the length of the nanowire to substantially coincide with at least one antinode of light resonating within the cavity. The active segment can be configured to interact with the light resonating within the cavity.
    Type: Application
    Filed: February 29, 2008
    Publication date: September 11, 2008
    Inventors: R. Stanley Williams, Shih-Yuan Wang, Philip J. Kuekes, Theodore I. Kamins, Duncan Stewart, Alexandre M. Bratkovski, Jason Blackstock, Zhiyong Li
  • Publication number: 20080180786
    Abstract: A metamaterial structure for light processing includes a light guide and a composite resonant electromagnetic (EM) structure having a resonant frequency. The composite resonant EM structure is arranged to interact with light propagating along the light guide to upconvert a frequency of the light to the resonant frequency, which generates second and higher harmonics of the light frequency. Methods of processing light are also disclosed.
    Type: Application
    Filed: January 30, 2007
    Publication date: July 31, 2008
    Inventor: Alexandre M. Bratkovski
  • Patent number: 7405866
    Abstract: An apparatus for controlling propagation of incident electromagnetic radiation is described, comprising a composite material having electromagnetically reactive cells of small dimension relative to a wavelength of the incident electromagnetic radiation. At least one of a capacitive and inductive property of at least one of the electromagnetically reactive cells is temporally controllable to allow temporal control of an associated effective refractive index encountered by the incident electromagnetic radiation while propagating through the composite material.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: July 29, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Philip J Kuekes, Shih-Yuan Wang, Raymond G Beausoleil, Alexandre M. Bratkovski, Wei Wu, M. Saif Islam
  • Patent number: 7397558
    Abstract: Methods of forming NERS-active structures are disclosed that include ordered arrays of nanoparticles. Nanoparticles covered with an outer shell may be arranged in an ordered array on a substrate using Langmuir-Blodgett techniques. A portion of the outer shell may be removed, and the exposed nanoparticles may be used in a system to perform nanoenhanced Raman spectroscopy. An ordered array of nanoparticles may be used as a mask for forming islands of NERS-active material on a substrate. NERS-active structures and an NERS system that includes an NERS-active structure are also disclosed. Also disclosed are methods for performing NERS with NERS-active structures.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: July 8, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Theodore I. Kamins, Alexandre M. Bratkovski, Shashank Sharma
  • Patent number: 7391511
    Abstract: A Raman signal-enhancing structure includes a substrate and a plurality of protrusions located at predetermined positions relative to a surface of the substrate. Each protrusion includes a Raman signal-enhancing material and has cross-sectional dimensions of less than about 50 nanometers. The structure also includes an edge that includes an intersection between two nonparallel surfaces of at least one protrusion. A Raman spectroscopy system includes such a Raman signal-enhancing structure, and Raman spectroscopy may be performed on an analyte using such structures and systems. A method for forming such a Raman signal-enhancing structure includes nanoimprint lithography.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: June 24, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Shih-Yuan Wang, Zhiyong Li
  • Publication number: 20080108000
    Abstract: Materials and methods for fabricating and using negative index materials are disclosed. A negative index material comprises a three-dimensional volume including a bulk solution and a plurality of unit cells disposed in the bulk solution in a substantially random pattern. Each unit cell comprises a periodic hole array pattern on a substrate or a resonator formed on a first surface of a substrate, and a thin wire pattern formed on a second surface of the substrate. The combination of the unit cells in the bulk solution produces a negative effective permeability and a negative effective permittivity over a frequency band of interest for the three-dimensional volume. The negative index material may be used to focus radiation by directing an incident radiation at the negative index material and generating a focused radiation by a negative refraction of the incident radiation in the negative index material.
    Type: Application
    Filed: October 20, 2006
    Publication date: May 8, 2008
    Inventors: Wei Wu, Shih-Yuan Wang, Alexandre M. Bratkovski
  • Publication number: 20080100345
    Abstract: Various method and system embodiments of the present invention are directed to implementing serial logic gates using nanowire-crossbar arrays with spintronic devices located at nanowire-crossbar junctions. In one embodiment of the present invention, a nanowire-crossbar array comprises a first nanowire and a number of substantially parallel control nanowires positioned so that each control nanowire overlaps the first nanowire. The nanowire-crossbar array includes a number of spintronic devices. Each spintronic device is configured to connect one of the control nanowires to the first nanowire and operate as a latch for controlling signal transmissions between the control nanowire and the first nanowire.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 1, 2008
    Inventors: Alexandre M. Bratkovski, Wei Wu, Gregory S. Snider, R. Stanley Williams