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Signatures of two-photon pulses from a quantum two-level system

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 نشر من قبل Kevin Fischer
 تاريخ النشر 2017
  مجال البحث فيزياء
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The theoretical community has found interest in the ability of a two-level atom to generate a strong many-body interaction with light under pulsed excitation. Single-photon generation is the most well-known effect, where a short Gaussian laser pulse is converted into a Lorentzian single-photon wavepacket. However, recent proposals have surprisingly suggested that scattering with intense laser fields off a two-level atom may generate oscillations in two-photon emission that are out of phase with its Rabi oscillations, as the power of the pulse increases. Here, we provide an intuitive explanation for these oscillations using a quantum trajectory approach and show how they may preferentially result in emission of two-photon pulses. Experimentally, we observe signatures of these oscillations by measuring the bunching of photon pulses scattered off a two-level quantum system. Our theory and measurements provide crucial insight into the re-excitation process that plagues on-demand single-photon sources while suggesting the production of novel multi-photon states.



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