Generation of bright two-color continuous variable entanglement.

  title={Generation of bright two-color continuous variable entanglement.},
  author={Alessandro S. Villar and Luciano S. Cruz and Katiuscia Nadyne Cassemiro and Marcelo Martinelli and Paulo A. Nussenzveig},
  journal={Physical review letters},
  volume={95 24},
We present the first measurement of squeezed-state entanglement between the twin beams produced in an optical parametric oscillator operating above threshold. In addition to the usual squeezing in the intensity difference between the twin beams, we have measured squeezing in the sum of phase quadratures. Our scheme enables us to measure such phase anticorrelations between fields of different frequencies. In the present measurements, wavelengths differ by approximately 1 nm. Entanglement is… 

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Electronic address: nussen@if.usp

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