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arXiv · 0712.3271

Disentanglement of Source and Target and the Laser Quantum State

Changsuk Noh·H. J. Carmichael
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Abstract

Disentanglement of a laser source from its target qubit is proposed as a criterion establishing the laser quantum state as a coherent state. It is shown that the source-target density operator has a unique factorization in coherent states when the environmental record monitoring laser pump quanta is ignored. The source-target state conditioned upon the complete environmental record is entangled, though, as a state of known total quanta number (source plus target).

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Changsuk Noh, H. J. Carmichael. 2007-12-19. Disentanglement of Source and Target and the Laser Quantum State. https://doi.org/10.1103/physrevlett.100.120405

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