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arXiv · 1608.01571

Two-Photon Blockade in an Atom-Driven Cavity QED System

Christoph Hamsen·Karl Nicolas Tolazzi·Tatjana Wilk·Gerhard Rempe
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Abstract

Photon blockade is a dynamical quantum-nonlinear effect that occurs in driven systems with an anharmonic excitation ladder. For a single atom strongly coupled to an optical cavity, we show that driving the atom gives a decisively larger optical nonlinearity than driving the cavity. This enhances single-photon blockade and allows for the implementation of two-photon blockade where the absorption of two photons suppresses the absorption of further photons. As a signature, we report on three-photon antibunching with simultaneous two-photon bunching observed in the light emitted from the cavity. Our experiment constitutes a significant step towards multi-photon quantum-nonlinear optics.

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Christoph Hamsen, Karl Nicolas Tolazzi, Tatjana Wilk, Gerhard Rempe. 2017-03-24. Two-Photon Blockade in an Atom-Driven Cavity QED System. https://doi.org/10.1103/physrevlett.118.133604

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