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The goal of this project is to develop single photon source and detector measurement and calibration capabilities to support the emerging quantum industry and explore the lowest, quantum limits of photonic radiometry.



A portable system for calibrating the detection efficiency of superconducting nanowire single photon detectors.

Credit: Thomas Gerrits/NIST

For quantum applications, it is important to generate quantum states of light and detect them with extremely high efficiency. This project explores the metrology challenges associated with precision measurement of single photon sources and detectors. The classical photonic radiometry techniques used at NIST can determine absolute detector and source efficiencies to power levels as low as hundreds of picowatts (10 -10 Watts). However, the single photon detectors used in quantum industries typically are used at femtowatt (10 -15 Watt) power levels, and the light sources being measured can be in either classical or quantum photonic states. Detector calibrations for superconducting and single photon avalanche detectors have been demonstrated, and are being developed into commercially available services. Future research directions for this project include integration of true single photon sources, photon number resolving detectors, and waveguide integrated detectors and sources.

Project Publications

Created December 16, 2022, Updated January 4, 2023