3 ms·
It sounds terribly fishy... For anyone who tried doing any CCD astronomy, "1 photon per bit" sounds like an absolute lie.
by anovikov 6y ago
It sounds terribly fishy... For anyone who tried doing any CCD astronomy, "1 photon per bit" sounds like an absolute lie.
- opwieurposiu 6y agoThey use an amplifier to turn the one photon into many photons before the signal gets to the detector. For microwave, (current state of the art) they use a ruby maser[1]. In this scheme they use a Phase-sensitive fiber-optic amplifier[2]. [1] https://descanso.jpl.nasa.gov/monograph/series10/Reid_DESCANSO_sml-110804.pdf https://descanso.jpl.nasa.gov/monograph/series10/Reid_DESCAN... [2] https://www.laserfocusworld.com/fiber-optics/article/16548079/optical-amplifiers-phasesensitive-fiberoptic-amplifier-has-recordlow-11-db-noise https://www.laserfocusworld.com/fiber-optics/article/1654807... Edit: You can tell this stuff is black magic because it involves rare gems and cauldrons of liquid helium boiling off clouds of sinister vapors.
- lostmyoldone 6y agoSingle photon detectors have existed for a long timet - though not anywhere near those speeds afaik - hence the one bit part is not particularly strange, not as long as we're talking wavelengths close to visible light. The speed and ultra low noise seems spectacularly good, but then, if you can avoid electronics and heat+junction noise in preamp you're going to get good figures.