Tomographic markers and photon addition to coherent states of light: Comparison with experiment

Photon addition to quantized light is of immense interest, both experimentally and theoretically. We identify a set of markers that play an important role in the context of photon addition to coherent states of light. These markers are directly computable from optical tomograms. We calculate the amplification gain due to photon addition, and the dependence of quadrature variances on relevant parameters, from the tomograms and compare them with results obtained after state reconstruction in a recent experiment. Our results match well with the fidelity plots reported by the experimenters. Our approach which circumvents state reconstruction could provide a viable procedure to identify specific aspects of photon addition to nonclassical light as well, from the tomograms themselves.