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Generation of spatially broadband twin beams for quantum imaging

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 نشر من قبل Vincent Boyer
 تاريخ النشر 2007
  مجال البحث فيزياء
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We generate spatially multimode twin beams using 4-wave mixing in a hot atomic vapor in a phase-insensitive traveling-wave amplifier configuration. The far-field coherence area measured at 3.5 MHz is shown to be much smaller than the angular bandwidth of the process and bright twin images with independently quantum-correlated sub-areas can be generated with little distortion. The available transverse degrees of freedom form a high-dimensional Hilbert space which we use to produce quantum-correlated twin beams with finite orbital angular momentum.



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