Silicon photonics directional coupler design for non-deterministic C-NOT quantum gate implementation.

Frontini L., Armani F., Dao T. H., De Matteis F., Di Giuseppe G., Gunnella R., Iadanza S., Liberali V., Natali R., Palini L., Pergentili P., Salamon A., Shojaii J., Stabile A., Vitali D.
  Venerdì 16/09   09:00 - 13:30   Aula L - Christa Mc Auliffe   VI - Fisica applicata, acceleratori e beni culturali   Presentazione
Silicon photonics opens the way for an easy integration of complex optical systems in the telecom C-band with integrated electronic circuits and for quantum computation purposes. This contribution will focus on the simulation results of a Photonic Circuit (PC) presently under fabrication within INFN QUANTEP project. Our PC contains several configurations of an integrated Directional Coupler realized with rectangular silicon waveguide (height $220 {nm}$, width $450 {nm}$). We will discuss the results of the simulations, focusing on how the transmission and reflection factors of the DC depend on waveguide's gap, coupling lengths and curvature. This first batch PC, realized for lithographic tuning purposes, represents an intermediate step towards the fabrication of a universal two-qubit Controlled-NOT (C-NOT) gate which is the simplest universal quantum gate. The simulation results, evaluated in a classical light framework with the Lumerical FDTD software, will be compared against the experimental results from the prototype chip. Attention will be paid to the simulation of edge coupling for light insertion and extraction with optical fibers connecting the PC to sources and detectors.