Generating Nonclassical States from Classical Radiation by Subtraction Measurements

TL;DR

This paper proposes a method to generate nonclassical microwave states using ideal photon detection with back action, enabling creation of states like squeezed and cat states from coherent radiation, with potential experimental implementation.

Contribution

It introduces a protocol leveraging photon subtraction measurements to produce diverse nonclassical microwave states from classical sources.

Findings

The protocol can generate squeezed states.

It can produce multi-component cat states.

Applicability to Josephson Photomultiplier experiments is discussed.

Abstract

We describe the creation of nonclassical states of microwave radiation via ideal dichotomic single photon detection, i.e., a detector that only indicates presence or absence of photons. Ideally, such a detector has a back action in the form of the subtraction operator. Using the non-linearity of this back action, it is possible to create a large family of nonclassical states of microwave radiation, including squeezed and multi-component cat states, starting from a coherent state. We discuss the applicability of this protocol to current experimental designs of Josephson Photomultipliers (JPMs).