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Single Photon Detector Comparison in a Quantum Key Distribution Link Testbed



Jonathan L. Habif, David S. Pearson, Robert Hadfield, Robert E. Schwall, Sae Woo Nam, Aaron J. Miller


We provide a direct comparison between the InGaAs avalanche photodiode (APD) and the NbN superconducting single photon detector (SSPD) for applications in fiber-based quantum cryptography. The quantum efficiency and dark count rate were measured for each detector, and used to calculate the quantum bit error rate (QBER) for a QKD link. The results indicate that, despite low quantum efficiency, the speed of the SSPD makes it a superior detector for quantum information applications. Finally, we demonstrate successful key exchange in the BBN QKD link using an SSPD to receive key material.
Applied Physics Letters


BB84, QKD, quantum communication, quantum key distribution, superconducting single photon detector


Habif, J. , Pearson, D. , Hadfield, R. , Schwall, R. , Nam, S. and Miller, A. (2006), Single Photon Detector Comparison in a Quantum Key Distribution Link Testbed, Applied Physics Letters, [online], (Accessed April 13, 2024)
Created October 24, 2006, Updated October 12, 2021