A Systems Theory Approach to the Synthesis of Minimum Noise Phase-Insensitive Quantum Amplifiers

TL;DR

This paper introduces a systems theory framework for designing quantum amplifiers that add minimal noise, providing a synthesis method for constructing such amplifiers with specified gain and bandwidth using quantum optical components.

Contribution

It offers a novel systems theory approach to prove bounds on quantum noise and a practical synthesis procedure for minimal noise quantum amplifiers.

Findings

Derived bounds on quantum noise in phase-insensitive amplifiers

Developed a synthesis method involving squeezers and beamsplitters

Constructed a minimal noise amplifier with specified gain and bandwidth

Abstract

We present a systems theory approach to the proof of a result bounding the required level of added quantum noise in a phase-insensitive quantum amplifier. We also present a synthesis procedure for constructing a quantum optical phase-insensitive quantum amplifier which adds the minimum level of quantum noise and achieves a required gain and bandwidth. This synthesis procedure is based on a singularly perturbed quantum system and leads to an amplifier involving two squeezers and two beamsplitters.