Enhancing photon squeezing one Leviton at a time

TL;DR

This paper compares different periodic voltage drives in mesoscopic quantum devices and finds that Lorentzian pulses best enhance quantum squeezing and entanglement, advancing quantum information applications.

Contribution

It introduces a detailed comparison of drive shapes in photon squeezing, highlighting Lorentzian pulses as optimal for quantum feature enhancement.

Findings

Lorentzian pulses improve quantum squeezing.

Rectangular and cosine drives are less effective.

Enhanced purity of photon states with Lorentzian drive.

Abstract

A mesoscopic device in the simple tunnel junction or quantum point contact geometry emits microwaves with remarkable quantum properties, when subjected to a sinusoidal drive in the GHz range. In particular, single and two-photon squeezing as well as entanglement in the frequency domain have been reported. By revising the photo-assisted noise analysis developed in the framework of electron quantum optics, we present a detailed comparison between the cosine drive case and other experimentally relavent periodic voltages such as rectangular and Lorentzian pulses. We show that the latter drive is the best candidate in order to enhance quantum features and purity of the outgoing single and two-photon states, a noteworthy result in a quantum information perspective.