Patents by Inventor Ehsan Shah Hosseini

Ehsan Shah Hosseini 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: 20170315387
    Abstract: An optical phase shifter may include a waveguide core that has a top surface, and a semiconductor contact that is laterally displaced relative to the waveguide core and is electrically connected to the waveguide core. A top surface of the semiconductor contact is above the top surface of the waveguide core. The waveguide core may include a p-type core region and an n-type core region. A p-type semiconductor region may be in physical contact with the n-type core region of the waveguide core, and an n-type semiconductor region may be in physical contact with the p-type core region of the waveguide core. A phase shifter region and a light-emitting region may be disposed at different depth levels, and the light-emitting region may emit light from a phase shifter region that is in a position adjacent to the light-emitting region.
    Type: Application
    Filed: April 27, 2017
    Publication date: November 2, 2017
    Inventors: Michael R. WATTS, Ehsan SHAH HOSSEINI, Christopher Vincent POULTON, Erman TIMURDOGAN
  • Publication number: 20170315420
    Abstract: An optical device may include at least two waveguides with different propagation constants. Each waveguide is associated with a grating antenna with a grating period selected to emit light at the same emission angle despite the different propagation constants. Each waveguide may be part of an optical path that includes phase shifters. Additionally, the waveguides may be formed in a waveguide layer that is separate from a perturbation layer in which the grating antennas as formed.
    Type: Application
    Filed: April 27, 2017
    Publication date: November 2, 2017
    Inventors: Michael R. WATTS, Ehsan SHAH HOSSEINI, Christopher Vincent POULTON, Erman TIMURDOGAN
  • Patent number: 9806485
    Abstract: Examples of the present invention include integrated erbium-doped waveguide lasers designed for silicon photonic systems. In some examples, these lasers include laser cavities defined by distributed Bragg reflectors (DBRs) formed in silicon nitride-based waveguides. These DBRs may include grating features defined by wafer-scale immersion lithography, with an upper layer of erbium-doped aluminum oxide deposited as the final step in the fabrication process. The resulting inverted ridge-waveguide yields high optical intensity overlap with the active medium for both the 980 nm pump (89%) and 1.5 ?m laser (87%) wavelengths with a pump-laser intensity overlap of over 93%. The output powers can be 5 mW or higher and show lasing at widely-spaced wavelengths within both the C- and L-bands of the erbium gain spectrum (1536, 1561 and 1596 nm).
    Type: Grant
    Filed: February 24, 2016
    Date of Patent: October 31, 2017
    Assignee: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Purnawirman Purnawirman, Michael R. Watts, Ehsan Shah Hosseini, Jonathan B. Bradley, Jie Sun, Matteo Cherchi
  • Publication number: 20170219776
    Abstract: A photodetector includes a germanium layer evanescently coupled to a ring resonator. The ring resonator increases the interaction length between light guided by the ring resonator and the germanium layer without increasing the size of the photodetector, thereby keeping the photodetector's dark current at a low level. The germanium layer absorbs the guided light and converts the absorbed light into electrical signals for detection. The increased interaction length in the resonator allows efficient transfer of light from the resonator to the germanium layer via evanescently coupling. In addition, the internal and external quality factors (Q) of the ring resonator can be matched to achieve (nearly) full absorption of light in the germanium with high quantum efficiency.
    Type: Application
    Filed: January 30, 2017
    Publication date: August 3, 2017
    Inventors: Erman Timurdogan, Michael R. Watts, Zhan Su, Ehsan Shah Hosseini, Jie Sun
  • Publication number: 20160248216
    Abstract: Examples of the present invention include integrated erbium-doped waveguide lasers designed for silicon photonic systems. In some examples, these lasers include laser cavities defined by distributed Bragg reflectors (DBRs) formed in silicon nitride-based waveguides. These DBRs may include grating features defined by wafer-scale immersion lithography, with an upper layer of erbium-doped aluminum oxide deposited as the final step in the fabrication process. The resulting inverted ridge-waveguide yields high optical intensity overlap with the active medium for both the 980 nm pump (89%) and 1.5 ?m laser (87%) wavelengths with a pump-laser intensity overlap of over 93%. The output powers can be 5 mW or higher and show lasing at widely-spaced wavelengths within both the C- and L-bands of the erbium gain spectrum (1536, 1561 and 1596 nm).
    Type: Application
    Filed: February 24, 2016
    Publication date: August 25, 2016
    Inventors: Purnawirman Purnawirman, Michael R. Watts, Ehsan Shah Hosseini, Jonathan B. Bradley, Jie Sun, Matteo Cherchi
  • Patent number: 9325140
    Abstract: Examples of the present invention include integrated erbium-doped waveguide lasers designed for silicon photonic systems. In some examples, these lasers include laser cavities defined by distributed Bragg reflectors (DBRs) formed in silicon nitride-based waveguides. These DBRs may include grating features defined by wafer-scale immersion lithography, with an upper layer of erbium-doped aluminum oxide deposited as the final step in the fabrication process. The resulting inverted ridge-waveguide yields high optical intensity overlap with the active medium for both the 980 nm pump (89%) and 1.5 ?m laser (87%) wavelengths with a pump-laser intensity overlap of over 93%. The output powers can be 5 mW or higher and show lasing at widely-spaced wavelengths within both the C- and L-bands of the erbium gain spectrum (1536, 1561 and 1596 nm).
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: April 26, 2016
    Assignee: Massachusetts Institute of Technology
    Inventors: Purnawirman Purnawirman, Michael R. Watts, Ehsan Shah Hosseini, Jonathan D. B. Bradley, Jie Sun, Matteo Cherchi