Patents by Inventor Tadaaki Nagao

Tadaaki Nagao 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: 10996172
    Abstract: Surface-functionalized nano structures, arrays of the nanostructures, and method for using the arrays in surfaced-enhanced spectroscopy and dielectric sensing applications, such as surface-enhanced infrared absorption spectroscopy, are provided. The nanostructures are functionalized with specific binding moieties that are bound to the nanostructures via phosphonic acid linkers.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: May 4, 2021
    Assignees: NATIONAL INSTITUTE OF MATERIAL SCIENCE, Northwestern University
    Inventors: Robert P. H. Chang, Shiqiang Li, Peijun Guo, Kai Chen, Keiko Okano, Tadaaki Nagao
  • Publication number: 20200292910
    Abstract: An optical deflector includes; a light transmitting portion through which a light passes; and a pair of electrodes arranged to oppose to each other with the light transmitting portion interposed therebetween. The light transmitting portion is a transparent ion conductor made of a single crystal or polycrystal. The pair of electrodes apply a predetermined voltage to the light transmitting portion to move ions inside the transparent ion conductor so as to change a traveling direction of the light passing through the light transmitting portion.
    Type: Application
    Filed: March 5, 2020
    Publication date: September 17, 2020
    Inventors: Yosuke SUZUKI, Tadaaki NAGAO, Akio WATANABE
  • Publication number: 20200141871
    Abstract: Surface-functionalized nano structures, arrays of the nanostructures, and method for using the arrays in surfaced-enhanced spectroscopy and dielectric sensing applications, such as surface-enhanced infrared absorption spectroscopy, are provided. The nanostructures are functionalized with specific binding moieties that are bound to the nanostructures via phosphonic acid linkers.
    Type: Application
    Filed: April 27, 2018
    Publication date: May 7, 2020
    Inventors: Robert P. H. Chang, Shiqiang Li, Peijun Guo, Kai Chen, Keiko Okano, Tadaaki Nagao
  • Publication number: 20200048548
    Abstract: The present invention has for its object to provide a composition in which a photoluminescent carbon nanoparticle having no dependency of an emission wavelength on an excitation wavelength and being enhanced in terms of quantum efficiency is dispersed, a process of producing the same, and an application of the same. The composition of the invention has a photoluminescent carbon nanoparticle dispersed in a water-soluble solvent. The photoluminescent carbon nanoparticle contains a carbon atom, an oxygen atom, a nitrogen atom, and a hydrogen atom if required. As shown in FIG. 6, the photoluminescent carbon nanoparticle has an intensity of a C—N bond and/or C—O bond-derived peak (285.98 eV) larger than that of a C—C bond and/or C—H bond-derived peak (284.95 eV) in terms of X-ray photoelectron spectroscopic spectra, and a Raman spectrum having a peak based on a G-band and a D-band.
    Type: Application
    Filed: March 1, 2018
    Publication date: February 13, 2020
    Inventors: Tadaaki NAGAO, Karuna Kar NANDA
  • Patent number: 10290802
    Abstract: The forming voltage of a variable resistance device used in a non-volatile memory and the like is decreased, and repetition characteristics are improved. In an element structure in which a metal oxide film is sandwiched between a lower electrode and an upper electrode, an island-shaped/particulate region of amorphous aluminum oxide or aluminum oxycarbide is formed on the metal oxide film. Because an oxide deficiency, serving as the nucleus of a filament for implementing an on/off operation of the variable resistance device, is formed from the beginning under the island-shaped or particulate aluminum oxide or the like, the conventional creation of an oxide deficiency by high-voltage application in the initial period of forming can be eliminated. Such a region can be fabricated using a small number of cycles of an ALD process.
    Type: Grant
    Filed: January 13, 2016
    Date of Patent: May 14, 2019
    Assignee: National Insitute for Materials Science
    Inventors: Toshihide Nabatame, Tadaaki Nagao
  • Patent number: 10067270
    Abstract: The present invention relates to an electromagnetic wave absorbing/radiating material which includes: a conductor; and a plurality of conductor discs disposed in an array above the surface of the conductor or a perforated conductor layer with a plurality of holes defined in an array above the surface of the conductor.
    Type: Grant
    Filed: August 10, 2015
    Date of Patent: September 4, 2018
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Tadaaki Nagao, Thang Duy Dao, Takahiro Yokoyama, Satoshi Ishii
  • Publication number: 20170346006
    Abstract: The forming voltage of a resistance change element used in a non-volatile memory and the like is decreased, and repetition characteristics are improved. In an element structure in which a metal oxide film 12 is sandwiched between a lower electrode 11 and an upper electrode 14, an island/particle-like region of amorphous aluminum oxide or aluminum oxycarbide 13 is formed on the metal oxide film 12. Because an oxide deficiency, serving as the nucleus of a filament for implementing an on/off operation of the resistance change element, is formed from the beginning under the island- or particle-like aluminum oxide or the like, the conventional creation of an oxide deficiency by high-voltage application in the initial period of forming can be eliminated. Such a region can be fabricated using a small number of cycles of an ALD process.
    Type: Application
    Filed: January 13, 2016
    Publication date: November 30, 2017
    Applicant: National Institute for Materials Science
    Inventors: Toshihide NABATAME, Tadaaki NAGAO
  • Publication number: 20170219746
    Abstract: The present invention relates to an electromagnetic wave absorbing/radiating material which includes: a conductor; and a plurality of conductor discs disposed in an array above the surface of the conductor or a perforated conductor layer with a plurality of holes defined in an array above the surface of the conductor.
    Type: Application
    Filed: August 10, 2015
    Publication date: August 3, 2017
    Inventors: Tadaaki Nagao, Thang Duy Dao, Takahiro Yokoyama, Satoski Ishii
  • Patent number: 8193499
    Abstract: The method for producing a surface enhanced infrared absorption sensor of the invention is characterized by: adsorbing metallic nanoparticles dispersed in a solution on a surface of a substrate, or allowing the adsorbed metallic nanoparticles to be grown in a solution, thereby forming a film; applying infrared light to the substrate from the side thereof opposite to the side on which the metallic nano-thin film is disposed; detecting evanescent waves exuding from the substrate; and regulating a surface enhanced infrared adsorption activity while monitoring surface enhanced infrared adsorption signals in situ, whereby the metallic nano-thin film is grown in the form of flat and discontinuous islands. According to the method, there is provided a production technique for a surface enhanced infrared absorption (SEIRA) sensor having a higher sensitivity and more excellent in the reproducibility.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: June 5, 2012
    Assignee: National Institute for Materials Science
    Inventors: Tadaaki Nagao, Dominik Enders, Tomonobu Nakayama, Masakazu Aono
  • Publication number: 20100239821
    Abstract: The method for producing a surface enhanced infrared absorption sensor of the invention is characterized by: adsorbing metallic nanoparticles dispersed in a solution on a surface of a substrate, or allowing the adsorbed metallic nanoparticles to be grown in a solution, thereby forming a film; applying infrared light to the substrate from the side thereof opposite to the side on which the metallic nano-thin film is disposed; detecting evanescent waves exuding from the substrate; and regulating a surface enhanced infrared adsorption activity while monitoring surface enhanced infrared adsorption signals in situ, whereby the metallic nano-thin film is grown in the form of flat and discontinuous islands. According to the method, there is provided a production technique for a surface enhanced infrared absorption (SEIRA) sensor having a higher sensitivity and more excellent in the reproducibility.
    Type: Application
    Filed: September 5, 2008
    Publication date: September 23, 2010
    Inventors: Tadaaki Nagao, Dominik Enders, Tomonobu Nakayama, Masakazu Aono
  • Patent number: 6946674
    Abstract: A low-dimensional plasmon-light emitter for converting an inputted electric energy luminescence with an arbitrary energy over a broad range. The emitter has a low-dimensional conductive structure incorporated inside or in a surface layer of a semiconductor or dielectric. A periodic nanostructure is incorporated in the vicinity of or inside the low-dimensional conductive structure. The low-dimensional conductive structure may be a quantum well formed inside a semiconductor or dielectric, a space-charge layer formed on a surface or heterojunction of a semiconductor or dielectric, or a surface or interface electronic band with high carrier density formed on a surface or heterojunction of a semiconductor or dielectric.
    Type: Grant
    Filed: March 11, 2002
    Date of Patent: September 20, 2005
    Assignee: Japan Science and Technology Corporation
    Inventor: Tadaaki Nagao
  • Publication number: 20040079938
    Abstract: A low-dimensional plasmon-light emitter, which can convert an inputted electric energy to luminescent with an arbitrary energy over a broad range from a far-infrared region to an ultraviolet region, has a low-dimensional conductive structure incorporated inside or in a surface layer of a semiconductor or dielectric. A periodic nanostructure, which has a periodicity corresponding to a real space periodicity D1(=2&pgr;/q1), wherein a wavenumber q1 gives a specified luminescent energy (h/2&pgr;1)&ohgr;1 in a wavenumber-energy curve of low-dimensional plasmon, is incorporated in the vicinity of or inside the low-dimensional conductive structure. The low-dimensional conductive structure may be a quantum well formed inside a semiconductor or dielectric, a space-charge layer formed on a surface or heterojunction of a semiconductor or dielectric or a surface or interface electronic band with high carrier density formed on a surface or heterojunction of a semiconductor or dielectric.
    Type: Application
    Filed: September 11, 2003
    Publication date: April 29, 2004
    Inventor: Tadaaki Nagao