| 摘要 |
PROBLEM TO BE SOLVED: To provide a quantum-entangled photon pair generating device for generating a quantum-entangled photon pair having high purity without generating excessive excess loss by using a general and simple optical component. SOLUTION: The quantum-entangled photon pair generating device has a polarization-maintaining loop optical path having a polarization separation multiplexing module as both ends, and a secondary nonlinear optical medium having a secondary nonlinear optical effect is placed in the loop optical path. Input excited light is branched into two branched excited light orthogonal to each other and input in the loop optical path in reverse directions. The secondary nonlinear optical medium performs SHG (Second Harmonic Generation) conversion and SPDC (Spontaneous Parametric down-conversion) conversion on the branched excited light irrespective of input directions to generate natural parametric down-conversion light. Two spontaneous parametric down-conversion light propagated in both directions are multiplexed and output by the polarization separation multiplexing module and after that, signal light and idler light are separated and extracted. The loop optical path includes a polarization plane operating means operating a polarization direction of at least a portion of an optical component so that the above multiplexing is performed. COPYRIGHT: (C)2011,JPO&INPIT |
