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The Quantum State of an Ideal Propagating Laser Field

S. J. van Enk·Christopher A. Fuchs
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Abstract

We give a quantum information-theoretic description of an ideal propagating CW laser field and reinterpret typical quantum-optical experiments in light of this. In particular we show that contrary to recent claims [T. Rudolph and B. C. Sanders, Phys. Rev. Lett. 87, 077903 (2001)], a conventional laser can be used for quantum teleportation with continuous variables and for generating continuous-variable entanglement. Optical coherence is not required, but phase coherence is. We also show that coherent states play a priveleged role in the description of laser light.

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S. J. van Enk, Christopher A. Fuchs. 2001-12-05. The Quantum State of an Ideal Propagating Laser Field. https://doi.org/10.1103/physrevlett.88.027902

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