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).

  • Patent number: 8542518
    Abstract: An optically-controlled memory resistor includes (1) a memory resistor having a first electrode, a second electrode, and a photo-responsive active layer disposed between the first and second electrodes and (2) a light source in cooperation with the memory resistor. The light source is configured to controllably illuminate the memory resistor for affecting a resistance state exhibited by the memory resistor. Also, a method for operating a memory resistor includes changing a resistance state of the memory resistor in response to an application of photons to the memory resistor.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: September 24, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Iakov Veniaminovitch Kopelevitch
  • Publication number: 20130222557
    Abstract: Image viewing systems are disclosed. In one aspect, an image viewing system includes a screen (108, 208, 302, 402, 502, 602, 808) and a projection system (304) that includes at least one video projector (310, 410, 510, 610, 810), and at least two mirrors (311, 411, 511, 611, 811) associated with each video projector (310, 410, 510, 610, 810). The projection system (304) projects different perspective views of images onto the screen (108, 208, 302, 402, 502, 602, 808). The at least two mirrors are oriented in at least two different orientations to redirect the path of light rays from the associated video projector (310, 410, 510, 610, 810) to the screen (108, 208, 302, 402, 502, 602, 808), enabling a viewer looking at the screen (108, 208, 302, 402, 502, 602, 808) to view successive views of each image.
    Type: Application
    Filed: November 1, 2010
    Publication date: August 29, 2013
    Applicant: Hewlett-Packard Development Company, L.P.
    Inventors: Huei Pei Kuo, Alexandre M. Bratkovski, Nelson Liang An Chang
  • Publication number: 20130215495
    Abstract: A nanoparticle waveguide apparatus, a nanoparticle waveguide photonic system and a method of photonic transmission employ a nearfield-coupled nanoparticle (NCN) waveguide to cooperatively propagate an optical signal. The nanoparticle waveguide apparatus includes a first optical waveguide adjacent to a second optical waveguide, the first optical waveguide comprising an NCN waveguide having a plurality of nanoparticles. The nanoparticle waveguide photonic system further includes a nearfield coupling (NC) modulator. The method includes providing the NCN waveguides and modulating a coupling between one or both of first and second NCN waveguides and adjacent nanoparticles within one or both of the first and second NCN waveguides.
    Type: Application
    Filed: October 29, 2010
    Publication date: August 22, 2013
    Inventors: Lars H. Thylen, Alexandre M. Bratkovski, Petter Holmstrom
  • Publication number: 20130207069
    Abstract: A metal-insulator transition switching device includes a first electrode and a second electrode. A channel region which includes a bulk metal-insulator transition material separates the first electrode and the second electrode. A method for forming a metal-insulator transition switching device includes depositing a layer of bulk metal-insulator transition material in between a first electrode and a second electrode to form a channel region and forming a gate electrode operatively connected to the channel region.
    Type: Application
    Filed: October 21, 2010
    Publication date: August 15, 2013
    Inventors: Matthew D. Pickett, Philip J. Kuekes, R. Stanley Williams, Frederick Perner, Wei Wu, Alexandre M. Bratkovski
  • Patent number: 8476647
    Abstract: A silicon-germanium, quantum-well, light-emitting diode. The light-emitting diode includes a p-doped portion, a quantum-well portion, and an p-doped portion. The quantum-well portion is disposed between the p-doped portion and the n-doped portion. The quantum-well portion includes a carrier confinement region that is configured to facilitate luminescence with emission of light produced by direct recombination with a hole confined within the carrier confinement region. The p-doped portion includes a first alloy of silicon-germanium, and the n-doped portion includes a second alloy of silicon-germanium.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: July 2, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Viatcheslav Osipov
  • Patent number: 8477303
    Abstract: A reconfigurable surface enhanced Raman spectroscopy (SERS) apparatus, system and method employ a stimulus responsive material to move nanorods of a plurality between inactive and active configurations. The apparatus includes the plurality of nanorods and the stimulus responsive material. The system further includes a Raman signal detector. The method of reconfigurable SERS includes providing the plurality of nanorods and exposing the stimulus responsive material to a stimulus. The exposure causes a change in one or more of a size, a shape and a volume of the stimulus responsive material that moves the nanorods between the inactive and active configurations. The active configuration facilitates one or both of production and detection of a Raman scattering signal emitted by the analyte.
    Type: Grant
    Filed: January 26, 2011
    Date of Patent: July 2, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M Bratkovski, Wei Wu, Zhiyong Li
  • Patent number: 8471270
    Abstract: An indirect-bandgap-semiconductor, light-emitting diode. The indirect-bandgap-semiconductor, light-emitting diode includes a plurality of portions including a p-doped portion of an indirect-bandgap semiconductor, an intrinsic portion of the indirect-bandgap semiconductor, and a n-doped portion of the indirect-bandgap semiconductor. The intrinsic portion is disposed between the p-doped portion and the n-doped portion and forms a p-i junction with the p-doped portion, and an i-n junction with the n-doped portion. The p-i junction and the i-n junction are configured to facilitate formation of at least one hot electron-hole plasma in the intrinsic portion when the indirect-bandgap-semiconductor, light-emitting diode is reverse biased and to facilitate luminescence produced by recombination of a hot electron with a hole.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: June 25, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Viatcheslav Osipov
  • Patent number: 8472018
    Abstract: Systems and methods employ a layer having a pattern that provides multiple discrete guided mode resonances for respective couplings of separated wavelengths into the layer. Further, a structure including features shaped to enhance Raman scattering to produce light of the resonant wavelengths can be employed with the patterned layer.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: June 25, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael J. Stuke, Michael R. T. Tan, Alexandre M. Bratkovski, Min Hu, Huei Pei Kuo, Jingjing Li, Zhiyong Li, Fung Suong Ou, Shih-Yuan Wang, Wei Wu
  • Patent number: 8459797
    Abstract: This disclosure is directed to rear projection and front projection image viewing systems. In one aspect, an image viewing system includes a screen composed of a lens and a reflective diffuser with a microstructured surface. The system also includes an array of projectors. Each projector is to project an image onto the screen with a particular angle of incidence such that each image is to pass through the lens and is to be reflected back though the lens by the reflective diffuser with a horizontal scattering angle determined by the microstructured surface. The lens is to direct each reflected image to a particular viewing area so that a viewer located in at least one viewing area receives a reflected image that enters one or both of the viewer's eyes when the viewer looks at the screen.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: June 11, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Huei Pei Kuo, Alexandre M. Bratkovski
  • Patent number: 8446661
    Abstract: A resonant cavity with tunable nanowire. The resonant cavity includes a substrate. The substrate is coupleable to an optical resonator structure. The resonant cavity also includes a plurality of nanowires formed on the substrate. The plurality of nanowires is actuated in response to an application of energy.
    Type: Grant
    Filed: August 26, 2008
    Date of Patent: May 21, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Sagi Varghese Mathai, Alexandre M. Bratkovski, Wenhua Zhang, Shih-Yuan Wang
  • Publication number: 20130108207
    Abstract: A method includes fabricating a circuit element and a connection to the circuit element for a photonic integrated circuit. The method includes associating a configurable material with the circuit element and activating the configurable material via a poling rail and the connection to the circuit element during production of the integrated circuit.
    Type: Application
    Filed: October 28, 2011
    Publication date: May 2, 2013
    Inventors: Lars Helge Thylen, Michael Renne Ty Tan, Shih-Yuan Wang, Alexandre M. Bratkovski, Wayne V. Sorin, Michael Josef Stuke
  • Publication number: 20130108279
    Abstract: A laser communication system and method are disclosed. The laser communication system includes a laser receiver system to receive a frequency-shift keyed (FSK) optical signal encoded with a plurality of data signals. The laser receiver system including an FSK differential detection system that includes a plurality of differential detection filters that can each receive the FSK optical signal and generate an output. The FSK differential detection system can demodulate the FSK optical signal into a multi-bit digital code corresponding to a frequency of the FSK optical signal based on the output of each of the plurality of differential detection filters.
    Type: Application
    Filed: November 2, 2011
    Publication date: May 2, 2013
    Inventors: Alexandre M. Bratkovski, Jacob Khurgin
  • Publication number: 20130089288
    Abstract: A slot-line waveguide optical switch system and method are disclosed. An optical switch system can include a slot-line waveguide optical switch that includes a plurality of wall portions that are each formed from a high refractive-index material and that are arranged to form a channel portion comprising an electro-optic material interposed to extend between the plurality of wall portions. The channel portion can include an input channel to receive an input optical signal and plural output channels to receive the input optical signal from the input channel. A channel switching system can provide a voltage to an electrode coupled to a corresponding wall portion to change a relative refractive index in the output channels via the electro-optic material and thereby switch the input optical signal to one of the output channels.
    Type: Application
    Filed: October 10, 2011
    Publication date: April 11, 2013
    Inventors: LARS HELGE THYLEN, Michael Renne Ty Tan, Alexandre M. Bratkovski, Shih-Yuan Wang, Wayne V. Sorin, Michael Josef Stuke
  • Publication number: 20130057663
    Abstract: Various embodiments of the present invention are directed to image viewing systems. In one aspect, an image viewing system includes a projection system (104, 504, 604), and a dynamically reconfigurable screen (102, 502, 602). The projection system projects two or more images of perspective views of objects or a scene onto the screen.
    Type: Application
    Filed: April 30, 2010
    Publication date: March 7, 2013
    Inventors: Alexandre M. Bratkovski, Huei Pei Kuo, Peter George Hartwell
  • Patent number: 8390804
    Abstract: A surface enhanced Raman spectroscopy (SERS) apparatus, system and method employ a plurality of nanorods configured to vibrate. The apparatus includes the nanorods having tips at free ends opposite an end attached to a substrate. The tips are configured to adsorb an analyte and to vibrate at a vibration frequency. The apparatus further includes a vibration source configured to vibrate the free ends of the nanorods at the vibration frequency in a back-and-forth motion. Vibration of the nanorods is configured to facilitate detection of a Raman scattering signal emitted by the analyte adsorbed on the nanorod tips. The system further includes a synchronous detector configured to receive the Raman signal and to be gated cooperatively with the vibration of the nanorods. The method includes inducing a vibration of the nanorods, illuminating the vibrating tips to produce a Raman signal, and detecting the Raman signal using the detector.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: March 5, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael J. Stuke, Alexandre M. Bratkovski, Min Hu, Huei Pei Kuo, Jingjing Li, Zhiyong Li, Fung Suong Ou, Shih-Yuan (Sy) Wang, Wei Wu
  • Patent number: 8390705
    Abstract: A photodiode includes a first electrode, a second electrode, and a nanowire comprising a semiconductor core and a semiconductor shell. The nanowire has a first end and a second end, the first end being in electrical contact with the first electrode and the second end being in contact with the second electrode.
    Type: Grant
    Filed: October 27, 2009
    Date of Patent: March 5, 2013
    Assignee: Hewlett-Packard Develoment Company, L.P.
    Inventors: Alexandre M. Bratkovski, Vilatcheslav V. Osipov
  • Publication number: 20130037773
    Abstract: An ionic device includes a layer (220) of an ionic conductor containing first and second species (222, 224) of impurities. The first species (222) of impurity in the layer (220) is mobile in the ionic conductor, and a concentration profile of the first species (222) determines a functional characteristic of the device (200). The second species (224) of impurity in the layer (220) interacts with the first species (222) within the layer (220) to create a structure (226) that limits mobility of the first species (222) in the layer (220).
    Type: Application
    Filed: April 30, 2010
    Publication date: February 14, 2013
    Inventors: Dmitri B. Strukov, Alexandre M. Bratkovski, R. Stanley Williams, Zhiyong Li
  • Publication number: 20130033920
    Abstract: A device contains a first layer (420), a second layer (440); and a membrane (430) between the first and second layers (420, 440). Mobile ions (425) are in at least one of the first and second layers (420, 440), and the membrane (430) is permeable to the ions. Interfaces of the conductive membrane (430) with the first layer (420) and the second layer (440) are such that charge of a polarity of the ions (425) collects at the interfaces.
    Type: Application
    Filed: April 30, 2010
    Publication date: February 7, 2013
    Inventors: Dmitri B. Strukov, Alexandre M. Bratkovski, R. Stanley Williams, Michael R.T. Tan
  • Patent number: 8347726
    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: Grant
    Filed: April 25, 2007
    Date of Patent: January 8, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Nobuhiko P. Kobayashi, Shih-Yuan Wang, Alexandre M. Bratkovski, R. Stanley Williams
  • Publication number: 20130000688
    Abstract: A thermoelectric device (100) includes a pair of spaced apart oppositely doped structures (110, 120) connecting between a common electrode (140) at a first end and different ones of a pair (150) of separate electrodes (150a, 150b) at a second end of the structures. Each oppositely doped structure includes a first material (112, 122) of a respectively doped semiconductor bounded by a second material (114, 124, 116, 126). Boundaries (111, 121) between the respective first and second materials are parallel to a charge carrier conduction path between the common electrode and the separate electrodes. The respectively doped semiconductor has a thickness configured to be less than a phonon scattering length.
    Type: Application
    Filed: March 23, 2010
    Publication date: January 3, 2013
    Inventors: Hans S. Cho, Alexandre M. Bratkovski, Theodore I. Kamins