Patents by Inventor Shivashankar R. Vangala

Shivashankar R. Vangala 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: 20230327011
    Abstract: A high electron mobility transistor (HEMT) structure configured to generate a two-dimensional electron gas (2DEG) combined with a grating structure which interacts with the 2DEG when a bias voltage is applied across the HEMT structure to responsively generate Smith-Purcell radiation.
    Type: Application
    Filed: February 9, 2023
    Publication date: October 12, 2023
    Applicant: Government of the United States as Represented by the Secretary of the Air Force
    Inventors: John S Cetnar, David H Tomich, Shivashankar R Vangala
  • Patent number: 11543571
    Abstract: A transmission filter apparatus is provided that includes: (i) a substrate to serve as a foundation for the apparatus; (ii) a layer containing resonant dielectric cavities separated by conductive regions. The dimensions and design of the dielectric cavities, thickness of the layer, and substrate, dielectric and conductive materials are chosen to achieve resonant transmission of selected wavelengths. In a particular one or more embodiments, the layer is one dimensional, i.e. you have dielectric cavities along one axis in the plane that are comparatively infinity long in the parallel plane. In a particular one or more embodiments, the layer is two dimensional, i.e. you have dielectric cavities along both axis in the plane. The dimensions in each plane may or may not be equal. In a specific one or more embodiments, the dielectric cavities are terminated on the top and/or bottom by thin metal films with small apertures or tapers.
    Type: Grant
    Filed: June 16, 2020
    Date of Patent: January 3, 2023
    Assignee: United States of America as represented by the Secretary of the Air Force
    Inventors: Justin W. Cleary, Evan M. Smith, Ricky D. Gibson, Jr., Shivashankar R. Vangala, Joshua Hendrickson, Ivan Avrutsky
  • Publication number: 20220267927
    Abstract: A method of performing heteroepitaxy comprises exposing an OP-GaAs template in an HVPE reactor to a carrier gas, a first precursor gas, a second precursor gas (2pg), a Group II element, and a third precursor gas (3pg), to form an epitaxial growth of one of GaAs, GaP, and GaAsP directly on the OP-GaAs template; wherein the carrier gas is H2, wherein the first precursor is HCl, the Group II element is Ga; and wherein the second (V or VI group) precursor is one or more of AsH3 (arsine) and PH3 (phosphine), and the third precursor is one or more of PH3 and AsH3. For an epitaxial growth of GaAsP, the method may further comprise flowing the second and third precursors through the HVPE reactor at a 2pg:3pg ratio of about 1:0; heating the OP-template to 500° C.-900° C.; and gradually changing the 2pg:3pg ratio toward 0:1 over time.
    Type: Application
    Filed: February 22, 2021
    Publication date: August 25, 2022
    Inventors: Shivashankar R. Vangala, Vladimir Tassev
  • Publication number: 20210041612
    Abstract: A transmission filter apparatus is provided that includes: (i) a substrate to serve as a foundation for the apparatus; (ii) a layer containing resonant dielectric cavities separated by conductive regions. The dimensions and design of the dielectric cavities, thickness of the layer, and substrate, dielectric and conductive materials are chosen to achieve resonant transmission of selected wavelengths. In a particular one or more embodiments, the layer is one dimensional, i.e. you have dielectric cavities along one axis in the plane that are comparatively infinity long in the parallel plane. In a particular one or more embodiments, the layer is two dimensional, i.e. you have dielectric cavities along both axis in the plane. The dimensions in each plane may or may not be equal. In a specific one or more embodiments, the dielectric cavities are terminated on the top and/or bottom by thin metal films with small apertures or tapers.
    Type: Application
    Filed: June 16, 2020
    Publication date: February 11, 2021
    Inventors: Justin W. Cleary, Evan M. Smith, Ricky D. Gibson, Shivashankar R. Vangala, Joshua Hendrickson, Ivan Avrutsky
  • Patent number: 10422699
    Abstract: A hybrid plasmonic-pyroelectric detector and laser detection system is disclosed. The hybrid plasmonic-pyroelectric detector includes a substrate and a refractory ground plane mounted on a surface of the substrate. A plasmonic array defines a plurality of apertures formed in the array. A highly-oriented pyroelectric layer is mounted on a surface of the ground plane and a surface of the plasmonic array. The plasmonic array is constructed and arranged to select particular wavelengths. Alternatively, a semiconductor or an avalanche material may be used. A pair of electrode contacts are coupled to each of the plasmonic array and the refractory ground plane. A laser detection system in accordance with the disclosure includes a mechanical chopper, a lens, a folding mirror, and a chip carrier for mounting the hybrid plasmonic-pyroelectric detector.
    Type: Grant
    Filed: August 21, 2018
    Date of Patent: September 24, 2019
    Assignee: United States of America as represented by the Secretary of the Air Force
    Inventors: Jarrett H. Vella, Joshua Hendrickson, Justin W. Cleary, Shivashankar R. Vangala