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Demonstration of a Low-Noise Near-Infrared Photon Counter with Multiphoton Discrimination



Aaron J. Miller, Sae Woo Nam, John M. Martinis, A. Sergeinko


We have demonstrated a system capable of directly measuring the photon-number state of a single pulse of light using a superconducting transition-edge sensor microcalorimeter. We verify the photon-number distribution of a weak pulsed-laser source at 1550 nm. Such single-photon metrology at telecommunications wavelengths provides the foundation for ensuring the security of photon sources used in implementations of quantum cryptography. Additionally, this system has the photon sources used in lowest noise equivalent power of any single-photon detector and combines high efficiency near-infrared photon counting with the ability to resolve multiphoton absorption events.
Applied Physics Letters


photon counting, photon detectors, photon number, quantum computing, quantum cryptography, quantum information, quantum key distribution, superconducting detectors, telecommunications


Miller, A. , Nam, S. , Martinis, J. and Sergeinko, A. (2003), Demonstration of a Low-Noise Near-Infrared Photon Counter with Multiphoton Discrimination, Applied Physics Letters (Accessed July 14, 2024)


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Created July 27, 2003, Updated October 12, 2021