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: 20110188755
    Abstract: A pattern recognition system includes an active media, an input system, and a sensing system. The active media is such that initial states respectively evolve over time to distinguishable final states. The input system establishes in the active media in an initial state corresponding to an input pattern, and the sensing system measures the media at separated locations to identify of which of the final states the media has after an evolution time. The identification of the final state indicates a feature of the input pattern.
    Type: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    Inventors: Alexandre M. Bratkovski, Viatcheslav Osipov, Ekaterina V. Ponizovskaya Devine
  • Publication number: 20110188034
    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: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    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
  • Publication number: 20110188035
    Abstract: A vibrating tip surface enhanced Raman spectroscopy (SERS) apparatus, system and method employ a nano-needle configured to vibrate. The apparatus includes the nano-needle with a substantially sharp tip at a free end opposite an end attached to a substrate. The tip is configured to adsorb an analyte. The apparatus further includes a vibration source configured to provide an alternating current (AC) electric field that induces a vibration of the free end and the tip of the nano-needle. Vibration of the nano-needle under the influence of the AC electric field facilitates detection of a Raman scattering signal from the analyte adsorbed on the nano-needle tip. The system further includes a synchronous detector configured to be gated cooperatively with the vibration of the nano-needle. The method includes inducing the vibration, illuminating the vibrating tip to produce a Raman signal, and detecting the Raman signal using the detector.
    Type: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    Inventors: Huei Pei Kuo, Michael J. Stuke, Min Hu, Fung Suong Ou, Shih-Yuan (SY) Wang, Alexandre M. Bratkovski, Wei Wu, Zhiyong Li
  • Patent number: 7991253
    Abstract: A device includes one or more waveguides and a memristive array adjacent to the waveguide(s). The memristive array is programmable to form a pattern that diffracts light and couples diffracted light into or out of the waveguide(s).
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: August 2, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Sagi V. Mathai
  • Patent number: 7989798
    Abstract: A patterned array of metallic nanostructures and fabrication thereof is described. A device comprises a patterned array of metallic columns vertically extending from a substrate. Each metallic column is formed by metallically coating one of an array of non-metallic nanowires catalytically grown from the substrate upon a predetermined lateral pattern of seed points placed thereon according to a nanoimprinting process. An apparatus for fabricating a patterned array of metallic nanostructures is also described.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: August 2, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Philip J Kuekes, M. Saif Islam, Shih-Yuan Wang, Alexandre M. Bratkovski
  • Patent number: 7989841
    Abstract: A fast injection optical switch is disclosed. The optical switch includes a thyristor having a plurality of layers including an outer doped layer and a switching layer. An area of the thyristor is configured to receive a light beam to be directed through at least one of the plurality of layers and exit the thyristor at a predetermined angle. At least two electrodes are coupled to the thyristor and configured to enable a voltage to be applied to facilitate carriers from the outer doped layer to be directed to the switching layer. Sufficient carriers can be directed to the switching layer to provide a change in refractive index of the switching layer to redirect at least a portion of the light beam to exit the thyristor at a deflection angle different from the predetermined angle.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: August 2, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Shih-Yuan Wang, Theodore I. Kamins
  • Publication number: 20110179880
    Abstract: A flow sensing system is provided. The system can include a first graphitic member and a first measurement device communicatively coupled to the first graphitic member. The first measurement device is adapted to measure a voltage along each of a plurality of orthogonal axes defined by the first graphitic member. The system can further include a display communicatively coupled to the first measurement device, the display adapted to convert the measured voltages into a signal proportionate to the fluid flow past the first graphitic member.
    Type: Application
    Filed: January 26, 2010
    Publication date: July 28, 2011
    Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Alexandre M. Bratkovski, Iakov Veniaminovitch Kopelevitch
  • Patent number: 7985962
    Abstract: A memristive device includes a first electrode, a second electrode, and an active region disposed between the first and second electrodes. At least one of the first and second electrodes is a metal oxide electrode.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: July 26, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexandre M. Bratkovski, Douglas Ohlberg, Jianhua Yang
  • Publication number: 20110169052
    Abstract: A non-volatile field-effect device. The non-volatile field-effect device includes a source, a drain, a channel-formation portion and a memristive gate. The channel-formation portion is disposed between and coupled with the source and the drain. The memristive gate is disposed over the channel-formation portion and coupled with the channel-formation portion. The memristive gate includes a plurality of mobile ions and a confinement structure for the plurality of mobile ions. Moreover, the memristive gate is configured to switch the channel-formation portion from a first conductivity state to a second conductivity state in response to migration of the plurality of mobile ions within the confinement structure.
    Type: Application
    Filed: January 11, 2010
    Publication date: July 14, 2011
    Inventors: Alexandre M. Bratkovski, R. Stanley Williams
  • Publication number: 20110168894
    Abstract: A photodetector for the detection of radiated electromagnetic energy includes at least one bolometer nanowire disposed at least partially within a photon trap. The at least one nanowire has at least one blackened surface. The blackened surface is configured to absorb radiated electromagnetic energy ranging from far-infrared light to visible light.
    Type: Application
    Filed: March 12, 2009
    Publication date: July 14, 2011
    Inventors: Alexandre M. Bratkovski, Viatcheslav V. Osipov
  • Publication number: 20110141546
    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: Application
    Filed: August 26, 2008
    Publication date: June 16, 2011
    Inventors: Sagi Varghese Mathai, Alexandre M. Bratkovski, Wenhua Zhang, Shih-Yuan Wang
  • Publication number: 20110141541
    Abstract: An active chiral photonic metamaterial having a dynamically controllable photonic material parameter is employed in a system and a method of polarization rotation. The active chiral photonic metamaterial includes a first chiral photonic element formed in a first metal layer, a second chiral photonic element formed in a second metal layer, and an active material layer disposed between the first and second metal layers. The active material layer includes the photonic material parameter that is dynamically controllable. A coupling between the first chiral photonic element and the second chiral photonic element is a function of the photonic material parameter of the active material layer. The system further includes a means for controlling the dynamically controllable photonic material parameter. The method includes illuminating the active chiral photonic metamaterial with an optical signal and applying a control signal to vary the dynamically controllable photonic material parameter.
    Type: Application
    Filed: December 15, 2009
    Publication date: June 16, 2011
    Inventor: Alexandre M. Bratkovski
  • Publication number: 20110096589
    Abstract: Embodiments of the present invention are directed to memristor devices that provide nonvolatile memristive switching. In one embodiment, a memristor device includes a first electrode, a second electrode, and a nanowire disposed between the first electrode and the second electrode. The nanowire is configured with an inner region surrounded by an outer layer. The memristor device may also include a mobile dopant confined to the inner region by repulsive electrostatic forces between the outer layer and the mobile dopant. The resistance of the nanowire is determined by the distribution of the mobile dopant in the inner region.
    Type: Application
    Filed: October 27, 2009
    Publication date: April 28, 2011
    Inventors: Alexandre M. Bratkovski, Viatcheslav Osipov
  • Publication number: 20110096218
    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: Application
    Filed: October 27, 2009
    Publication date: April 28, 2011
    Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Alexandre M. Bratkovski, Viatcheslav V. Osipov
  • Patent number: 7924413
    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: Grant
    Filed: February 29, 2008
    Date of Patent: April 12, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: R. Stanley Williams, Shih-Yuan Wang, Philip J. Kuekes, Theodore I. Kamins, Duncan Stewart, Alexandre M. Bratkovski, Jason Blackstock, Zhiyong Li
  • Publication number: 20110081109
    Abstract: A nanoparticle array photonic waveguide, a photonic transmission system and a method of photonic transmission compensate for optical loss in an optical signal through stimulated emission using an optical gain material in a core of composite nanoparticles. The nanoparticle array photonic waveguide includes a plurality of the composite nanoparticles arranged adjacent to one another in a row. A composite nanoparticle of the plurality includes a shell and a core. The shell includes a negative dielectric constant material that is capable of supporting an optical signal on a surface of the shell. The core is adjacent to a side of the shell opposite to the shell surface. The core includes an optical gain material (OGM) that is capable of providing optical gain to the optical signal through stimulated emission within the OGM.
    Type: Application
    Filed: October 5, 2009
    Publication date: April 7, 2011
    Inventors: Lars H. Thylen, Alexandre M. Bratkovski
  • Publication number: 20110075967
    Abstract: A system for routing optical signals includes a waveguide array and a cylindrical resonator lying across the waveguide array, the cylindrical resonator having independently controllable tangential interfaces with each of the waveguides within the waveguide array. A method of selectively routing an optical signal between waveguides includes selecting a optical signal to route; determining the desired path the optical signal; tuning a first controllable interface between a cylindrical resonator and a source waveguide to extract the optical signal from the source waveguide; and tuning a second independently controllable interface between the cylindrical resonator and a destination waveguide to deposit the optical signal into the destination waveguide.
    Type: Application
    Filed: June 9, 2008
    Publication date: March 31, 2011
    Inventors: Alexandre M. Bratkovski, Terrel Morris
  • Publication number: 20110024710
    Abstract: A memristor includes a substrate having a plurality of protrusions, wherein each of the plurality of protrusions extends in a first direction, a first electrode provided over at least one of the plurality of protrusions, wherein the first electrode conforms to the shape of the at least one protrusion such that the first electrode has a crest, a switching material positioned upon the first electrode; and a second electrode positioned upon the switching material such that a portion of the second electrode is substantially in line with the crest of the first electrode along the first direction, wherein an active region in the switching material is operable to be formed between the crest of the first electrode and the portion of the second electrode that is substantially in line with the crest of the first electrode.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 3, 2011
    Inventors: Alexandre M. Bratkovski, Shih Yuan Wang, Jianhua Yang, Michael Stuke
  • Publication number: 20110024716
    Abstract: A memristor includes a first electrode having a first surface, at least one electrically conductive nanostructure provided on the first surface, in which the at least one electrically conductive nanostructure is relatively smaller than a width of the first electrode, a switching material positioned upon said first surface, in which the switching material covers the at least one electrically conductive nanostructure, and a second electrode positioned upon the switching material substantially in line with the at least one electrically conductive nanostructure, in which an active region in the switching material is formed substantially between the at least one electrically conductive nanostructure and the first electrode.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 3, 2011
    Inventors: Alexandre M. Bratkovski, Qiangfei Xia, Jianhua Yang
  • Patent number: 7880251
    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: Grant
    Filed: April 26, 2007
    Date of Patent: February 1, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Shih-Yuan Wang, Alexandre M. Bratkovski