Overcoming the quantum limit of optical amplification in monolithic waveguides

TL;DR

This paper demonstrates a monolithic waveguide optical amplifier using third-order nonlinearity that surpasses the quantum noise limit in phase-sensitive mode, advancing integrated photonics for communications and quantum applications.

Contribution

It introduces a chip-scale parametric amplifier with noise performance below the quantum limit, a significant improvement over traditional amplifiers.

Findings

Achieved noise figure below the quantum limit in phase-sensitive operation

Demonstrated continuous-wave parametric amplification on a single chip

Showcased potential for applications in optical communications and quantum optics

Abstract

Optical amplifiers are essential in numerous photonic applications. Parametric amplifiers, relying on a nonlinear material to create amplification, are uniquely promising as they can amplify without generating excess noise. Here, we demonstrate amplification based on the 3rd order nonlinearity in a single chip, while in addition reporting a noise figure significantly below the conventional quantum limit when operated in phase-sensitive mode. Our results show the potential of nanophotonics for realizing continuous-wave parametric amplification that can enable applications in optical communications, signal processing and quantum optics across a wide range of frequencies.