Universal programmable photonic integrated circuits by interlacing phase shifters and Fourier transform units

Programmable photonic integrated circuits represent an emerging technology that amalgamates photonics and electronics, paving the way for light-based information processing at high speeds and low power consumption. Here, we present a novel architecture for efficient integrated photonic implementation of arbitrary matrix operations. The proposed architecture is built on interlacing discrete fractional Fourier transform layers with programmable phase shifter arrays. This circuit is resilient to defects in the phase shifters and perturbations in the intervening Fourier operators. We delve into the core attributes of this architectural design and explore its practical applications in the realm of analog information processing.