Patents by Inventor Dodd Joseph Gray

Dodd Joseph Gray 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: 11506951
    Abstract: Optical read-out of a cryogenic device (such as a superconducting logic or detector element) can be performed with a forward-biased optical modulator that is directly coupled to the cryogenic device without any intervening electrical amplifier. Forward-biasing at cryogenic temperatures enables very high modulation efficiency (1,000-10,000 pm/V) of the optical modulator, and allows for optical modulation with millivolt driving signals and microwatt power dissipation in the cryogenic environment. Modulated optical signals can be coupled out of the cryostat via an optical fiber, reducing the thermal load on the cryostat. Using optical fiber instead of electrical wires can increase the communication bandwidth between the cryogenic environment and room-temperature environment to bandwidth densities as high as Tbps/mm2 using wavelength division multiplexing.
    Type: Grant
    Filed: November 6, 2020
    Date of Patent: November 22, 2022
    Assignee: Massachusetts Institute of Technology
    Inventors: Rajeev J. Ram, Dodd Joseph Gray, Amir H. Atabaki, Marc De Cea Falco
  • Publication number: 20210208470
    Abstract: Optical read-out of a cryogenic device (such as a superconducting logic or detector element) can be performed with a forward-biased optical modulator that is directly coupled to the cryogenic device without any intervening electrical amplifier. Forward-biasing at cryogenic temperatures enables very high modulation efficiency (1,000-10,000 pm/V) of the optical modulator, and allows for optical modulation with millivolt driving signals and microwatt power dissipation in the cryogenic environment. Modulated optical signals can be coupled out of the cryostat via an optical fiber, reducing the thermal load on the cryostat. Using optical fiber instead of electrical wires can increase the communication bandwidth between the cryogenic environment and room-temperature environment to bandwidth densities as high as Tbps/mm2 using wavelength division multiplexing.
    Type: Application
    Filed: November 6, 2020
    Publication date: July 8, 2021
    Inventors: Rajeev J. RAM, Dodd Joseph GRAY, Amir H. Atabaki, Marc De Cea Falco
  • Patent number: 10205046
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage (e.g., V<kBT/q) can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: February 12, 2019
    Assignee: Massachusetts Institute of Technology
    Inventors: Parthiban Santhanam, Dodd Joseph Gray, Rajeev Jagga Ram
  • Publication number: 20170294551
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage (e.g., V<kBT/q) can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Application
    Filed: June 26, 2017
    Publication date: October 12, 2017
    Inventors: Parthiban Santhanam, Dodd Joseph GRAY, Rajeev Jagga RAM
  • Patent number: 9722144
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage (e.g., V<kBT/q) can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Grant
    Filed: August 14, 2014
    Date of Patent: August 1, 2017
    Assignee: Massachusetts Institute of Technology
    Inventors: Parthiban Santhanam, Dodd Joseph Gray, Rajeev Jagga Ram
  • Patent number: 9557215
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Grant
    Filed: August 16, 2013
    Date of Patent: January 31, 2017
    Assignee: Massachusetts Institute of Technology
    Inventors: Parthiban Santhanam, Dodd Joseph Gray, Rajeev Jagga Ram
  • Publication number: 20150311401
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage (e.g., V<kBT/q) can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Application
    Filed: August 14, 2014
    Publication date: October 29, 2015
    Applicant: Massachusetts Institute of Technology
    Inventors: Parthiban Santhanam, Dodd Joseph Gray, Rajeev Jagga Ram
  • Publication number: 20140159582
    Abstract: Contrary to conventional wisdom, which holds that light-emitting diodes (LEDs) should be cooled to increase efficiency, the LEDs disclosed herein are heated to increase efficiency. Heating an LED operating at low forward bias voltage (e.g., V<kBT/q) can be accomplished by injecting phonons generated by non-radiative recombination back into the LED's semiconductor lattice. This raises the temperature of the LED's active rejection, resulting in thermally assisted injection of holes and carriers into the LED's active region. This phonon recycling or thermo-electric pumping process can be promoted by heating the LED with an external source (e.g., exhaust gases or waste heat from other electrical components). It can also be achieved via internal heat generation, e.g., by thermally insulating the LED's diode structure to prevent (rather than promote) heat dissipation. In other words, trapping heat generated by the LED within the LED increases LED efficiency under certain bias conditions.
    Type: Application
    Filed: August 16, 2013
    Publication date: June 12, 2014
    Inventors: Parthiban Santhanam, Dodd Joseph Gray, Rajeev Jagga Ram