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Absolute efficiency and time-response measurement of single-photon detectors
Applied Optics
|October 2, 2010
Summary
Researchers achieved record single-photon detector efficiencies up to 76.4% using correlated photons. An auxiliary mirror boosted efficiency, and detector timing responses were analyzed.
Area of Science:
- Quantum optics
- Photonics
- Detector physics
Background:
- Accurate characterization of single-photon detectors is crucial for quantum information science.
- Previous studies reported lower quantum efficiencies for photon detectors.
Purpose of the Study:
- To measure absolute quantum efficiencies and time responses of single-photon detectors.
- To evaluate the impact of a retroreflection mirror on detection efficiency.
- To investigate detector performance under various conditions, including afterpulses and saturation.
Main Methods:
- Utilized correlated photons generated via spontaneous parametric downconversion (SPDC).
- Employed a coincidence counting technique to analyze detector performance.
- Measured absolute quantum efficiencies and temporal profiles of four single-photon detectors.
Main Results:
- Achieved single-photon detection efficiencies as high as (76.4 ± 2.3)% at 702 nm, the highest reported to date.
- Observed a net detection efficiency increase by a factor of 1.19 with an auxiliary retroreflection mirror.
- Characterized detector time responses, with the narrowest coincidence peak showing a 300 ps full width at half maximum (FWHM).
- Investigated afterpulses, saturation effects, and the influence of varying device parameters.
Conclusions:
- The study demonstrates a significant advancement in single-photon detector technology.
- The findings provide valuable data for optimizing detector performance in quantum experiments.
- The use of correlated photons offers a robust method for precise detector characterization.
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