Science
In reply to the discussion: Quantum Entanglement, Dark Counts, Coincidence Detection [View all]caraher
(6,278 posts)Those are the ones that run ~$1500 or so to members of the ALPhA, the advanced lab group under the umbrella of the American Association of Physics Teachers.
How important the dark count rate is depends on your expected "true" count rate. If you need to know singles rates to great precision then you want to pay extra for low dark counts; but if you either expect a lot of counts or only really care about coincidences, you need not pay top dollar for low dark counts. Also bear in mind that the specs are upper limits, and the devices often outperform the specs substantially. I think they just build them all and sort them based on test results, so if they have a model promising 250 Hz and another at 500 Hz what that generally means is that the cheaper one will come in somewhere between 250 and 500 Hz. I think mine were spec'ed at 500 Hz and give me 350-450 Hz for dark counts