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arXiv · 0803.3784

Observation of entanglement between two light beams spanning an octave in optical frequency

Nicolai B. Grosse·Syed Assad·Moritz Mehmet·Roman Schnabel·Thomas Symul·Ping Koy Lam
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Abstract

We have experimentally demonstrated how two beams of light separated by an octave in frequency can become entangled after their interaction in a second-order nonlinear medium. The entangler consisted of a nonlinear crystal placed within an optical resonator that was strongly driven by coherent light at the fundamental and second-harmonic wavelengths. An inter-conversion between the fields created quantum correlations in the amplitude and phase quadratures, which were measured by two independent homodyne detectors. Analysis of the resulting correlation matrix revealed a wavefunction inseparability of 0.74(1) < 1 thereby satisfying the criterion of entanglement.

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Nicolai B. Grosse, Syed Assad, Moritz Mehmet, Roman Schnabel, Thomas Symul, Ping Koy Lam. 2008-03-26. Observation of entanglement between two light beams spanning an octave in optical frequency. https://doi.org/10.1103/physrevlett.100.243601

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