Continuous variable entanglement enhancement and manipulation by a sub-threshold type-II optical parametric amplifier

Abstract

We experimentally demonstrate that the quantum entanglement between amplitude and phase quadratures of optical modes produced from a non-degenerate optical parametric amplifier (NOPA) can be enhanced and manipulated phase-sensitively by means of another NOPA. When both NOPAs operate at de-amplification, the entanglement degree is increased at the cavity resonance of the second NOPA. When the first NOPA operates at de-amplification and the second one at amplification, the spectral features of the correlation variances are significantly changed. The experimental results are in good agreement with the theoretical expectation.

References in corpus (5)

• Increasing entanglement between Gaussian states by coherent photon subtraction
• Full characterization of Gaussian bipartite entangled states by a single homodyne detector
• Experimental continuous-variable entanglement from a phase-difference-locked optical parametric oscillator
• Phase-sensitive Manipulations of Squeezed Vacuum Field in an Optical Parametric Amplifier inside an Optical Cavity
• Experimental demonstration of frequency-degenerate bright EPR beams with a self-phase-locked optical parametric oscillator