Scalable feedback control of single-photon sources for photonic quantum technologies

A frequency-stabilized single-photon source comprising:

• a microring resonator with a nonlinear material to generate a single photon in response to being pumped with a pump beam;
• a filter, in optical communication with the microring resonator, to filter the single photon from the pump beam;
• a detector, in optical communication with the filter, to detect an intensity of the pump beam;
• a phase shifter, operably coupled to the detector and the microring resonator, to tune a wavelength of a resonance of the microring resonator based on the intensity of the pump beam;
• a first pump laser to generate pump light at a first wavelength;
• a second pump laser to generate pump light at a second wavelength greater than the first wavelength;
• and
• a beam combiner, in optical communication with the first pump laser and the second pump laser, to combine the pump light at the first wavelength and the pump light at the second wavelength to form the pump beam.

A frequency-stabilized single-photon source, comprising:

• a first microring resonator with a nonlinear material to generate a first single photon in response to being pumped with a first pump beam;
• a first filter, in optical communication with the first microring resonator, to filter the first single photon from the first pump beam;
• a first detector, in optical communication with the first filter, to detect an intensity of the first pump beam;
• a first phase shifter, operably coupled to the first detector and the first microring resonator, to tune a wavelength of a resonance of the first microring resonator based on the intensity of the first pump beam;
• a second microring resonator to generate a second single photon in response to being pumped with a second pump beam;
• a second filter, in optical communication with the second microring resonator, to filter the second single photon from the second pump beam;
• a second detector, in optical communication with the second filter, to detect an intensity of the second pump beam;
• and
• a second phase shifter, operably coupled to the second detector and the second microring resonator, to tune a resonance frequency of the second microring resonator based on the intensity of the second pump beam.

A photonic device comprising:

• a substrate;
• an array of microring resonators, integrated on the substrate and comprising χ3 nonlinear material, to generate single photons at a signal wavelength in response to being pumped with pump light at a first pump wavelength greater than the signal wavelength and a second pump wavelength less than the signal wavelength;
• an array of filters integrated on the substrate, each filter in the array of filters in optical communication with a corresponding microring resonator in the array of microring resonators and configured to filter the single photon from light at the first pump wavelength and at the second pump wavelength coupled out of the corresponding microring resonator;
• an array of detectors in optical communication with the array of filters, each detector in the array of detectors in optical communication with a corresponding filter in the array of filters and configured to detect an intensity of the light at the first pump wavelength and/or at the second pump wavelength filtered by the corresponding filter;
• and
• an array of thermo-optic modulators integrated on the substrate, each thermo-optic modulator in the array of thermo-optic modulators operably coupled to a corresponding detector in the array of detectors and in thermal communication with the corresponding microring resonator and configured to stabilize a resonance frequency of the corresponding microring resonator based on the intensity detected by the corresponding detector.