Patents Assigned to Axalume, Inc.
  • Patent number: 10826272
    Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a first optical waveguide, a first ring resonator that selectively optically coupled to a second optical waveguide and that performs phase modulation and filtering of the optical signal, the second optical waveguide, an amplitude modulator, and an output port. Note that the reflective layer in the optical gain chip and the amplitude modulator may define an optical cavity. Furthermore, a resonance of the first ring resonator may be aligned with a lasing wavelength, and the resonance of the first ring resonator and a resonance of the amplitude modulator may be offset from each other. Additionally, modulation of the first ring resonator and the amplitude modulator may be in-phase with each other.
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: November 3, 2020
    Assignee: Axalume, Inc.
    Inventors: Jock Bovington, Xuezhe Zheng, Saman Saeedi, Ashok V. Krishnamoorthy
  • Patent number: 10714895
    Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a common optical waveguide, a splitter that splits the optical signal into optical signals, a first pair of resonators that are selectively optically coupled to the common optical waveguide and that are configured to perform modulation and filtering of the optical signals, and a first bus optical waveguide that is selectively optically coupled to the first pair of resonators. Furthermore, resonance wavelengths of the resonators may be offset from each other with a (e.g., fixed) separation approximately equal or corresponding to a modulation amplitude, and a reflectivity of the first pair of resonators may be approximately independent of the modulation.
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: July 14, 2020
    Assignee: Axalume, Inc.
    Inventors: Ashok V. Krishnamoorthy, Jock Bovington, Xuezhe Zheng, Saman Saeedi
  • Patent number: 10447013
    Abstract: A high-power packaged laser array that is thermal reflow compatible is described. Notably, a high-power III-V laser array is integrated on a silicon substrate with a matching array of ball lenses, an isolator and a coupler (such as a reflective layer) to achieve an edge-coupled or a surface-normal output laser array. In some embodiments, an isolator with a permanent magnet is used to preserve the magnetic domain or state of the isolator during the thermal reflow(s), which can involve temperatures up to 250 C. In order to relax the misalignment tolerance when integrating with the silicon chip, a laser array with a larger optical mode may be used to increase the output beam size. Moreover, a III-V laser array with an angled output optical waveguide can be used to improve the stability of the lasers at high power.
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: October 15, 2019
    Assignee: Axalume, Inc.
    Inventors: Xuezhe Zheng, John E. Cunningham, Ashok V. Krishnamoorthy
  • Patent number: 10419128
    Abstract: An integrated circuit that includes an optical receiver is described. This integrated circuit may include an optical receiver. The optical receiver may include a photodiode that receives an optical signal and that outputs a corresponding current. Moreover, the optical receiver may include an inductor that is electrically coupled to the photodiode. Furthermore, the optical receiver may include a resistive analog front-end stage that is electrically coupled to the inductor. Note that the inductor may have a resistance per unit length that is greater than a first threshold value (such as 40 m?/?m), and the inductor may be approximately dispersion-less. For example, a Q factor for inductive peaking associated with the inductor is less than a second threshold value (such as 5).
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: September 17, 2019
    Assignee: Axalume, Inc.
    Inventors: Saman Saeedi, Ashok V. Krishnamoorthy
  • Patent number: 10365432
    Abstract: An integrated circuit that reduces back reflection of an optical signal is described. This integrated circuit may convey an optical signal in an optical waveguide defined in a layer in the integrated circuit. The integrated circuit may split the optical signal into portions of the optical signal using an optical splitter, and may convey the portions of the optical signal in at least two arms of the optical waveguide. Then, the integrated circuit may establish a predefined phase offset between the portions of the optical signal using at least a phase-offset device in one of the two arms. Furthermore, the integrated circuit may optically couple the portions of the optical signal at optical coupling interfaces at ends of the two arms. Note that the predefined phase offset may reduce the back reflection of the optical signal at the optical splitter to less than a threshold value.
    Type: Grant
    Filed: April 21, 2018
    Date of Patent: July 30, 2019
    Assignee: Axalume, Inc.
    Inventor: Jock Bovington
  • Patent number: 10193636
    Abstract: A DC-coupled burst-mode optical receiver is described. The optical receiver may include an input node that receives a current, e.g., from an optoelectronic converter (such as a photodiode). Moreover, the optical receiver may include a current amplifier, coupled to the input node, that provides an output current based at least in part on the current, where the current amplifier has a shunt feedback path that reduces a bias sensitivity of the current amplifier and a feed-forward path that reduces a DC bias current of the current amplifier. Furthermore, the optical receiver may include a TIA, electrically coupled to the current amplifier, that converts the output current to an output voltage. Additionally, the optical receiver may include a feedback loop coupling an output of the TIA to an input of the feed-forward path.
    Type: Grant
    Filed: April 21, 2018
    Date of Patent: January 29, 2019
    Assignee: Axalume, Inc.
    Inventors: Saman Saeedi, Ashok V. Krishnamoorthy
  • Publication number: 20190027899
    Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a common optical waveguide, a splitter that splits the optical signal into optical signals, a first pair of resonators that are selectively optically coupled to the common optical waveguide and that are configured to perform modulation and filtering of the optical signals, and a first bus optical waveguide that is selectively optically coupled to the first pair of resonators. Furthermore, resonance wavelengths of the resonators may be offset from each other with a (e.g., fixed) separation approximately equal or corresponding to a modulation amplitude, and a reflectivity of the first pair of resonators may be approximately independent of the modulation.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: Axalume, Inc.
    Inventors: Ashok V. Krishnamoorthy, Jock Bovington, Xuezhe Zheng, Saman Saeedi
  • Publication number: 20190027898
    Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a first optical waveguide, a first ring resonator that selectively optically coupled to a second optical waveguide and that performs phase modulation and filtering of the optical signal, the second optical waveguide, an amplitude modulator, and an output port. Note that the reflective layer in the optical gain chip and the amplitude modulator may define an optical cavity. Furthermore, a resonance of the first ring resonator may be aligned with a lasing wavelength, and the resonance of the first ring resonator and a resonance of the amplitude modulator may be offset from each other. Additionally, modulation of the first ring resonator and the amplitude modulator may be in-phase with each other.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: Axalume, Inc.
    Inventors: Jock Bovington, Xuezhe Zheng, Saman Saeedi, Ashok V. Krishnamoorthy
  • Publication number: 20190027901
    Abstract: A high-power packaged laser array that is thermal reflow compatible is described. Notably, a high-power III-V laser array is integrated on a silicon substrate with a matching array of ball lenses, an isolator and a coupler (such as a reflective layer) to achieve an edge-coupled or a surface-normal output laser array. In some embodiments, an isolator with a permanent magnet is used to preserve the magnetic domain or state of the isolator during the thermal reflow(s), which can involve temperatures up to 250 C. In order to relax the misalignment tolerance when integrating with the silicon chip, a laser array with a larger optical mode may be used to increase the output beam size. Moreover, a III-V laser array with an angled output optical waveguide can be used to improve the stability of the lasers at high power.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: Axalume, Inc.
    Inventors: Xuezhe Zheng, John E. Cunningham, Ashok V. Krishnamoorthy
  • Publication number: 20190028207
    Abstract: An integrated circuit that includes an optical receiver is described. This integrated circuit may include an optical receiver. The optical receiver may include a photodiode that receives an optical signal and that outputs a corresponding current. Moreover, the optical receiver may include an inductor that is electrically coupled to the photodiode. Furthermore, the optical receiver may include a resistive analog front-end stage that is electrically coupled to the inductor. Note that the inductor may have a resistance per unit length that is greater than a first threshold value (such as 40 m?/?m), and the inductor may be approximately dispersion-less. For example, a Q factor for inductive peaking associated with the inductor is less than a second threshold value (such as 5).
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: Axalume, Inc.
    Inventors: Saman Saeedi, Ashok V. Krishnamoorthy