2006/10/15 by Peter van Loock, Christian Weedbrook, Mile Gu
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physreva.76.032321
published as Phys. Rev. A 76, 032321 (2007). · 5 Pages, 3 figures
arxiv created 2006/10/15 · arxiv updated 2009/12/01
The linear optical creation of Gaussian cluster states, a potential resource for universal quantum computation, is investigated. We show that for any Gaussian cluster state, the canonical generation scheme in terms of QND-type interactions, can be entirely replaced by off-line squeezers and beam splitters. Moreover, we find that, in terms of squeezing resources, the canonical states are rather wasteful and we propose a systematic way to create cheaper states. As an application, we consider Gaussian cluster computation in multiple-rail encoding. This encoding may reduce errors due to finite squeezing, even when the extra rails are achieved through off-line squeezing and linear optics.