Quantum Advantage in Optical Laser Communications using NISQ-era Quantum Processors

Abstract: Optical laser communication forms a cornerstone of modern-day data communications. In the quantum-limited regime of lasercom, where the received optical signal power is small, e.g., in deep-space communications, pre-detection quantum domain collective processing of blocks of received signal pulses corresponding to communication codewords can provide enhanced communication capacity. We present a novel quantum receiver design methodology based on a quantum belief propagation algorithm that attains such enhancement. I will discuss the receiver design and the feasibility of implementing the receiver using noisy intermediate-scale non-error-corrected quantum processors of the type currently being developed in the quantum computing industry.