2007/04/30 by Marco G. Genoni, Matteo G. A. Paris, Konrad Banaszek · 1 citation
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physreva.76.042327
published as Phys. Rev. A 76, 042327 (2007) · revised and enlarged version, 7 pages, 4 figures
arxiv created 2007/10/02 · arxiv updated 2009/12/01
We address the issue of quantifying the non-Gaussian character of a bosonic quantum state and introduce a non-Gaussianity measure based on the Hilbert-Schmidt distance between the state under examination and a reference Gaussian state. We analyze in details the properties of the proposed measure and exploit it to evaluate the non-Gaussianity of some relevant single- and multi-mode quantum states. The evolution of non-Gaussianity is also analyzed for quantum states undergoing the processes of Gaussification by loss and de-Gaussification by photon-subtraction. The suggested measure is easily computable for any state of a bosonic system and allows to define a corresponding measure for the non-Gaussian character of a quantum operation.