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arXiv · 1111.0588

Gated Mode Superconducting Nanowire Single Photon Detectors

Mohsen K. Akhlaghi·A. Hamed Majedi
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Abstract

Single Photon Detectors (SPD) are fundamental to quantum optics and quantum information. Superconducting Nanowire SPDs (SNSPD) [1] provide high performance in terms of quantum efficiency (QE), dark count rate (DCR) and timing jitter [2], but have limited maximum count rate (MCR) when operated as a free-running mode (FM) detector [3, 4]. However, high count rates are needed for many applications like quantum computing [5] and communication [6], and laser ranging [7]. Here we report the first operation of SNSPDs in a gated mode (GM) that exploits a single photon triggered latching phenomenon to detect photons. We demonstrate operation of a large active area single element GM-SNSPD at 625MHz, one order of magnitude faster than its FM counterpart. Contrary to FM-SNSPDs, the MCR in GM can be pushed to GHz range without a compromise on the active area or QE, while reducing the DCR.

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quant-phphysics.ins-detphysics.optics

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BibTeXRIS

Mohsen K. Akhlaghi, A. Hamed Majedi. 2011-11-02. Gated Mode Superconducting Nanowire Single Photon Detectors. https://doi.org/10.1364/oe.20.001608

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