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arXiv · 1709.01120

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

Kevin A. Fischer·Lukas Hanschke·Jakob Wierzbowski·Tobias Simmet·Constantin Dory·Jonathan J. Finley·Jelena Vučković·Kai Müller
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Abstract

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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Kevin A. Fischer, Lukas Hanschke, Jakob Wierzbowski, Tobias Simmet, Constantin Dory, Jonathan J. Finley, Jelena Vučković, Kai Müller. 2017-09-04. Signatures of two-photon pulses from a quantum two-level system. https://doi.org/10.1038/nphys4052

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