A quantum superposition of two coherent states of light with small amplitude can be obtained by subtracting a photon from a squeezed vacuum state. In experiments this preparation can be made conditioned on the detection of a photon in the field from a squeezed light source. We propose and analyze an extended measurement strategy which allows generation of high fidelity coherent state superpositions with larger amplitude.
@article{arxiv.0708.1956,
title = {Transforming squeezed light into a large amplitude coherent state superposition},
author = {Anne E. B. Nielsen and Klaus Mølmer},
journal= {arXiv preprint arXiv:0708.1956},
year = {2014}
}