Quantum Path Computing and Communications with Fourier Optics.

Abstract

Multi-plane diffraction (MPD) systems with classical sources and conventional intensity detection are recently proposed for scalable quantum computing (QC) and communications (QComm) with time domain entanglement resources and by exploiting the energy efficient interference of exponentially increasing number of propagation paths. MPD provides unique advantages for the challenges of scalability of qubits and complex set-ups including single photon generation and detection mechanisms in state-of-the-art linear optics implementations. However, MPD based QC architectures denoted by quantum path computing (QPC) are theoretically modeled for only electron based system set-up with Gaussian sources while proposed classical communication architectures are defined for free space propagation without modeling for arbitrary Fourier optical set-ups being mathematically equivalent to linear canonical transforms (LCTs). In this article, MPD architectures are defined, theoretically modeled and numerically analyzed for Fourier optics with arbitrary LCTs between diffraction planes while utilizing both Gaussian and Hermite-Gaussian laser modes. Photonic MPD proposes QC and QComm based on the mature science of Fourier optics significantly developed since the last century with globally available resources for fast and wide spread development of the proposed design. It promises the simplest linear optical system with important QC applications while promising novel resources for classical and quantum communications.