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Experimental continuous-variable entanglement from a phase-difference-locked optical parametric oscillator

Jietai Jing·Sheng Feng·Russell Bloomer·Olivier Pfister
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Abstract

We observed continuous-variable entanglement between the bright beams emitted above threshold by an ultrastable optical parametric oscillator, classically phase-locked at a frequency difference of 161.8273240(5) MHz. The amplitude-difference squeezing is -3 dB and the phase-sum one is -1.35 dB. Besides proving entanglement in a new physical system, the phase-locked OPO, such unprecedented frequency-difference stability paves the way for transferring entanglement between different optical frequencies and densely implementing continuous-variable quantum information in the frequency domain.

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Jietai Jing, Sheng Feng, Russell Bloomer, Olivier Pfister. 2006-07-17. Experimental continuous-variable entanglement from a phase-difference-locked optical parametric oscillator. https://doi.org/10.1103/physreva.74.041804

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