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Generation of picosecond pulsed coherent state superpositions

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 نشر من قبل Ruifang Dong
 تاريخ النشر 2013
  مجال البحث فيزياء
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We present the generation of approximated coherent state superpositions - referred to as Schrodinger cat states - by the process of subtracting single photons from picosecond pulsed squeezed states of light at 830 nm. The squeezed vacuum states are produced by spontaneous parametric down-conversion (SPDC) in a periodically poled KTiOPO4 crystal while the single photons are probabilistically subtracted using a beamsplitter and a single photon detector. The resulting states are fully characterized with time-resolved homodyne quantum state tomography. Varying the pump power of the SPDC, we generated different states which exhibit non-Gaussian behavior.

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