Universal implementation of arbitrary unitary matrices by femtosecond laser written waveguide lattice

The integrated photonic platform has established itself as a versatile tool for experimental implementation of linear optical quantum computations, that base on unitary transformation of the input states. In this paper we investigate the potential application of the waveguide lattice architecture to realization of arbitrary unitary matrices. We propose a waveguide lattice construction and find its parameters using methods of numerical optimization. Also we showed that a necessary lattice parameters are within the reach femtosecond laser writing technology.