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It is often technologically important to know how photon statistics change over time when a light source is turned on. A light source that comes to full intensity/visibility in a nanosecond after it is turned on has different uses than a light source that takes a second to come to full intensity/visibility.

For the case of correlated two-photon Bell-state light sources, are there any characterizations of the increase of the visibility of Bell inequality violation after different types of such light sources are turned on? From a foundational point of view I'm interested in whether it takes a nanosecond or a second for the Bell violation to come to full visibility, but from a technical point of view I'm interested in whether different light sources have significantly different visibility curves when they are turned on.

Ultimately, I would like to see a characterization of the relationship of the emergence of visibility over time for the uncorrelated single photon component relative to the emergence of visibility over time for the two-photon Bell state component for different light sources.

I would also be interested in characterizations for the same light source but for different ways of interrupting (or modulating) the light source, instead of simply turning the power off and on.

This somewhat or perhaps largely duplicates my question "Do Bell inequality violations appear instantly when the source is turned on, or do they increase over time?" from the middle of last year, which received no answers or comments. [I hope this question is sufficiently more focused to elicit an answer or comments. I'd like an answer, not upvotes, for this question.]

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