Modeling of linear optical controlled-z quantum gate with dimensional errors of passive components

Linear optical quantum computing can be realized using photonic integrate circuits (PICs). It is advantageous in comparison to other physical implementations of quantum computing due to simplicity of qubit encoding using photons and low decoherence times. Passive components like beamsplitters and phaseshifters are key elements for such PICs. In this article, we present modeling of linear optical controlled-Z gate with imperfections of beamsplitters and phaseshifters taken into account. Results showed that errors occur which cannot be detected by projection measurements and post-selection proposed by Knill, Laflamme and Milburn. We studied how these errors and success probability changes with the increase of dimensional errors using Monte-Carlo simulation. The obtained results can be used for design and calibration stages of chip manufacturing.