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Pump depletion in parametric down-conversion with low pump energies

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 نشر من قبل Jefferson Fl\\'orez
 تاريخ النشر 2020
  مجال البحث فيزياء
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We report the efficient generation of high-gain parametric down-conversion, including pump depletion, with pump powers as low as 100 $mu$W (energies $0.1$~$mu$J/pulse) and conversion efficiencies up to 33%. In our simple configuration, the pump beam is tightly focused into a bulk periodically poled lithium niobate crystal placed in free space. We also observe a change in the photon number statistics for both the pump and down-converted beams as the pump power increases to reach the depleted pump regime. The experimental results are a clear signature of the interplay between the pump and the down-converted beams in highly efficient parametric down-conversion sources.

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