EPR correlation and quantum noise squeezing of output light fields from a narrowband NOPA

Summary form only given. Our calculation and experiment presented an indirect and undoubted path to demonstrate the quantum correlation between bright EPR beams, that bypassed the technical difficulty in these types of experiments. A system of nondegenerate optical parametric amplifiers (NOPA) in which the interconnected squeezed vacuum field, bright coherent-squeezed state light and EPR beams can be obtained simultaneously is also very interesting for practical applications.