Simple performance evaluation of pulsed spontaneous parametric down-conversion sources for quantum communications

TL;DR

This paper introduces a straightforward method for rapidly characterizing pulsed SPDC sources in quantum communications, requiring minimal measurements and modeling, and demonstrates its effectiveness through experimental validation.

Contribution

The paper presents a simple, measurement-based approach for evaluating SPDC sources, enabling quick assessment of key parameters without complex procedures.

Findings

Method accurately estimates pair emission probability

Effective in determining total losses and fidelity

Applicable to various bandwidths of SPDC sources

Abstract

Fast and complete characterization of pulsed spontaneous parametric down conversion (SPDC) sources is important for applications in quantum information processing and communications. We propose a simple method to perform this task, which only requires measuring the counts on the two output channels and the coincidences between them, as well as modeling the filter used to reduce the source bandwidth. The proposed method is experimentally tested and used for a complete evaluation of SPDC sources (pair emission probability, total losses, and fidelity) of different bandwidths. This method can find applications in the setting up of SPDC sources and in the continuous verification of the quality of quantum communication links.