Efficient Robust Spontaneous Parametric Down-Conversion via Detuning Modulated Composite Segments Designs

TL;DR

This paper introduces a composite design scheme for SPDC that significantly improves the stability and robustness of entangled photon pair generation, demonstrating a sevenfold enhancement against temperature fluctuations.

Contribution

The work develops a theoretical composite segments framework for SU(1,1) systems and experimentally applies it to enhance SPDC stability using a modulated KTP crystal.

Findings

Sevenfold improvement in photon-pair stability against temperature fluctuations

Enhanced error resilience in SPDC process

Applicable to other SU(1,1) physical systems

Abstract

Spontaneous Parametric Down Conversion (SPDC) holds a pivotal role in quantum physics, facilitating the creation of entangled photon pairs, heralded single photons and squeezed light, critical resources for many applications in quantum technologies. However, their production is susceptible to physical variations, posing limitations on their robust utility. To overcome these limitations, this work introduces a method to significantly enhance the reliability of entangled photon pair generation. This approach involves introducing a composite design scheme to the SPDC process. The design is based on the development of a theoretical composite segments framework for SU(1,1), offering increased error resilience and robustness of the process. The practical application is experimentally demonstrated by modulating the nonlinear coefficient of a KTP crystal for degenerate 532 nm to 1064 nm conversion, resulting in an effective sevenfold improvement in stability of photon-pair generation and coincidence rate against temperature fluctuations compared to conventional quasi-phase-matching techniques. Furthermore, the presented concept is applicable to other physical systems that exhibit SU(1,1) dynamics. This methodology can create a leap forward in quantum technologies by significantly enhancing stability and error tolerance, thus paving the way for a new generation of entangled photon sources, holding promise for quantum information processing, communication, and precision measurement applications.