| Continuous variable (CV) entangled states of light is essential resources in the research of continuous variable quantum information and quantum computation, the entangled states of light of quadrature amplitude and phase has been applied in the quantum information and computing research. People has completed many works with quantum entanglement, which can’t be completed with classical physics. Designing and realizing entanglement sources with potential application play very important role in the fundamental research and application of quantum optics. Phase-sensitive manipulation is the first manipulating action on quantum states of light, and the theoretical and experimental demonstration of the enhancement and manipulation of the squeezed states and EPR entangled states are realized by several groups. For a non-measurement-based coherent feedback control (CFC) system, it is regarded as a good way to manipulate the quantum states, because of not introducing any additional noise into the system. We theoretically proposed and experimentally realized the manipulation of the EPR entangled states by non-measurement-based coherent feedback control system. Though the CFC, the threshold pump power of non-degenerate optical parametric amplifier is reduced and the quantum entanglement degree of the output optical entangled states is improved at the same time. This will provide better reference on continuous variable quantum information research.In this thesis, the main research contents include:1. We theoretically design the manipulation system for EPR entangled states of light generated by NOPA via the coherent feedback control, and calculate the dependence of the quantum correlation noise of the output optical beams of the CFC-NOPA system on various parameters of system.2. We experimentally realize the EPR entanglement manipulation with CFC-NOPA system, and find that the entangled degree of the entangled states is increased from-3.5dB to-6dB through CFC. |
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