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Counting near-infrared single-photons with 95% efficiency



Adriana E. Lita, Aaron J. Miller, Sae Woo Nam


Single-photon detectors operating at visible and near-infrared wavelengths with high detection efficiency and low noise are a requirement for many quantum-information applications. Superconducting transition-edge sensors (TESs) are capable of detecting visible and near-infrared light at the single-photon level and are capable of discriminating between one-and two-photon absorption events; however these capabilities place stringent design requirements on the TES heat capacity, thermometry, and optical detection efficiency. We describe the fabrication and evaluation of a fiber-coupled, photon-number-resolving TES detector optimized for absorption at 1550 and 1310 nm wavelengths. The measured system detection efficiency at 1556 nm is 95% ± 2%, which to our knowledge is the highest system detection efficiency reported for a near-infrared singlephoton  detector.
Optics Express


optical design, single photon detectors
Created February 20, 2008, Updated February 17, 2017