Spatiotemproal effects on squeezing measurements

TL;DR

This paper investigates how spatiotemporal degrees of freedom affect the properties of squeezed photonic states generated by parametric down-conversion, revealing that increased efficiency can degrade the minimum uncertainty characteristic depending on measurement conditions.

Contribution

It introduces a functional approach under semi-classical and thin-crystal approximations to analyze the impact of spatiotemporal effects on squeezing measurements.

Findings

Squeezed states lose minimum uncertainty with higher down-conversion efficiency.

The degradation depends on homodyne measurement conditions.

Spatiotemporal effects are significant in squeezing measurements.

Abstract

The role of the spatiotemporal degrees of freedom in the preparation and observation of squeezed photonic states, produced by parametric down-conversion, is investigated. The analysis is done with the aid of a functional approach under the semi-classical approximation and the thin-crystal approximation. It is found that the squeezed state loses its minimum uncertainty property as the efficiency of down-conversion is increased, in a way that depends on the conditions of the homodyne measurements with which the amount of squeezing is determined.