Analysis of Errors in an Optical Controlled-NOT Gate

摘要

The errors in linear optics controlled not (C-NOT) gates are analyzed considering the polarization-dependent phase sifts, in addition to the incorrectness of the beam splitting ratios. It is shown that the phase sifts at the optical components is as crucial as other error sources discussed in the previous studies. Such a phase shift unintentionally changes the linearly-polarized photons into a elliptically polarized ones. The operators for a beam splitting device and the process matrix of the C-NOT operation including such errors are also given.