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arXiv · 1903.02041

Optical attenuation without absorption

I. C. Nodurft·R. A. Brewster·T. B. Pittman·J. D. Franson
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Abstract

We consider a coherent state of light propagating through an ensemble of two-level atoms where all the atoms are initially in their ground state. In ordinary absorption, the transition of atoms to their excited state along with the absorption of a photon will remove energy from the beam and attenuate the signal. Here we show that post-selecting on those cases in which none of the atoms made a transition to the excited state can give even more attenuation than would normally occur due to absorption. The same process can also produce amplification when there is a sufficiently strong interaction between the photons and the atoms.

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I. C. Nodurft, R. A. Brewster, T. B. Pittman, J. D. Franson. 2019-07-26. Optical attenuation without absorption. https://doi.org/10.1103/physreva.100.013850

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