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Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

Autoheterodyne Characterisation for Narrowband Photon-Pair Purity

Vindhiya Prakash, Aleksandra Sierant, Morgan W. Mitchell

Published Jun 26, 2023• 0 citations
Publisher

Abstract

Recently, there have been several advancements in the development of sources for narrowband non-classical light (with linewidth ≲ MHz). This is motivated by applications in quantum information and sensing where quantum light is interfaced with material quanta such as atoms or molecules. For instance, photonic quantum information processing can be realised through strong photon-photon interactions mediated by non-linearity in atoms and re-quires photon-pairs in which both photons are resonant and matched in bandwidth to an atomic transition. Applications in quantum networking, e.g. entanglement-swapping with memory-compatible photons, require the photons to be pure and indistinguishable in addition to being matched in frequency and bandwidth to quantum memories.

DOI
10.1109/cleo/europe-eqec57999.2023.10232560

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Quantum photonic entanglement generated from a photon-pair source is a crucial resource for many quantum technological implementations, for example, an entanglement-based global quantum network and metrology beyond classical limits. For the former, we require sufficient brightness to mitigate the loss to send the quantum state to a long distance. Additionally, to enable entanglement swapping, the heralded photons need to be spectrally pure and indistinguishable enabling high visibility quantum interference. Here, we discuss the required attributes and current benchmarks of the chip-scale photon-pair sources arguing that they are the prime candidate for the above applications.
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