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Enhancing LIDAR performance metrics using continuous-wave photon-pair sources

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 نشر من قبل Han Liu
 تاريخ النشر 2020
  مجال البحث فيزياء
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In order to enhance LIDAR performance metrics such as target detection sensitivity, noise resilience and ranging accuracy, we exploit the strong temporal correlation within the photon pairs generated in continuous-wave pumped semiconductor waveguides. The enhancement attained through the use of such non-classical sources is measured and compared to a corresponding target detection scheme based on simple photon-counting detection. The performances of both schemes are quantified by the estimation uncertainty and Fisher information of the probe photon transmission, which is a widely adopted sensing figure of merit. The target detection experiments are conducted with high probe channel loss ((simeq 1-5times10^{-5})) and formidable environment noise up to 36 dB stronger than the detected probe power of (1.64times 10^{-5}) pW. The experimental result shows significant advantages offered by the enhanced scheme with up to 26.3 dB higher performance in terms of estimation uncertainty, which is equivalent to a reduction of target detection time by a factor of 430 or 146 (21.6 dB) times more resilience to noise. We also experimentally demonstrated ranging with these non-classical photon pairs generated with continuous-wave pump in the presence of strong noise and loss, achieving (approx)5 cm distance resolution that is limited by the temporal resolution of the detectors.



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