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Waveguided sources of consistent, single-temporal-mode squeezed light: the good, the bad, and the ugly

Martin Houde, Nicolás Quesada

Published Jan 1, 2023• 0 citations
Publisher

Abstract

We study how variations in pump brightness, for identical profiles, affect the temporal-mode structure of squeezed states generated by three different waveguided sources. Double-pass structures give optimal results in terms of indistinguishability and spectral purity.
DOI
10.1364/cleo_fs.2023.ff1l.6

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We study theoretically how the brightness of the pumps, with fixed profiles, affects the temporal mode structure of squeezed states generated by fixed parametric waveguided sources. We find that the temporal modes of these squeezed states can be partially mismatched and thus distinguishable, which is undesirable when using these states as resources for quantum computing or heralded state generation. By studying common frequency filtering techniques used experimentally, we find that although one can regain indistinguishability, it comes at the price of potentially greatly reducing the purity of the state. We consider three different source configurations: unapodized single pass, apodized single pass, and apodized double pass. We find that the double pass configuration produces optimal results with almost perfectly indistinguishable states over varying degrees of brightness.
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