The Frequency Nondegenerate Parametric Amplifier as a Device to Analyze the Einstein-Podolsky-Rosen Paradox
There has been a growing interest in the past years to study the influence of losses on the quantum properties of light. In general, the optical fields of interest are not isolated, but interact with an external environment. Here we analyze the frequency nondegenerate parametric amplifier operating below threshold and damped by different cavity mirror transmission losses1. The Langevin approach is used to treat the mirror losses and the coupling to the external environment is taken into account through the input-output formalism. The extreme sensitivity of squeezing to this type of cavity losses is investigated, which is of great importance for experiments relying on the perfect correlations between twin photon beanis, like in the Einstein-Podolsky-Rosen (EPR) paradox 2. The possibility of demonstrating this paradox via quadrature measurements on the down-converted fields is evidenced through the dual local oscillator measurement scheme3, which allows to gain information about the quadrature phases of one of the output modes by performing balanced homodyne measurements on the other output field mode and is consequently well adapted for an EPR.-type experiment. It is our purpose to investigate the effects of different mirror transmission losses and frequency detuning of the outgoing fields on the demonstration of the EPR paradox, extending there by previous results restricted to frequency degenerate pairs of photons and symmetric transmission losses 4,5.