Noiseless attenuation using an optical parametric amplifier

TL;DR

This paper demonstrates that an optical parametric amplifier, when combined with heralding, can function as a noiseless attenuator, expanding the tools available for quantum communication applications.

Contribution

It introduces a novel method of implementing heralded noiseless attenuation using an optical parametric amplifier, differing from traditional beam-splitter approaches.

Findings

Optical parametric amplifier can be used as a heralded noiseless attenuator.

The approach leverages the probabilistic nature of the amplifier.

Potential applications in quantum communication are highlighted.

Abstract

The process of heralded noiseless amplification, and the inverse process of heralded noiseless attenuation, have potential applications in the context of quantum communications. Although several different physical implementations of heralded noiseless amplifiers have now been demonstrated, the research on heralded noiseless attenuators has been largely confined to a beam-splitter based approach. Here we show that an optical parametric amplifier (OPA), combined with appropriate heralding, can also serve as a heralded noiseless attenuator. The counterintuitive use of an optical amplifier as an attenuator is only possible due to the probabilistic nature of the device.