No, laser photon count statistics are Poissonian. There are fluctuations in photon detection rate. The distribution of photon energies is narrow (for a single spatial and temporal mode laser). Bruce
On Saturday, 7 May 2016 6:01 PM, Ilia Platone <i...@iliaplatone.com> wrote: Wait... no telescopes, very close distances... only a laser, with a photon limiter like a dark window, "close" like 10mm or so... just the space required for the laser optics plus the "limiter", and a photon counting detector that can be an APD or a PMT, it depends on the size required and scale of integration. The "idea" came because my professor told me that laser is a light source composed by a limited number of harmonics, so close the ones as some nm wavelengths, to get these lights can be directional and manouverable: if these should be the carachteristics of lasers (a laser expert can correct me), photons emitted by this type of light source should hit the detector at a constant rate. The (very dark) limiter serves to regulate the photon flux so a very limited number of photons reach the sensor part. The question was if the photodetector could use the individual photon detection as clock tick, and if these ticks can be regular in frequency. Many have replied that it would be noisy: phase noise? I don't think a single photon can cause AM noise, because I was talking about single photon pulses into the photon counting region, not into the analog region. Please correct me if I'm wrong. Ilia. Il 05/05/2016 21:22, Hal Murray ha scritto: > jim...@earthlink.net said: >> Well, in deep space optical comm, we send many photons with a laser, and we >> use pulse position modulation at the receiver detecting single photons (or >> "few photons"), by which we can send "many bits/photon" (e.g. if you have >> 256 possible time slots in which the photon can arrive, you have 8 bits/ >> photon) > Neat. Could you please say a bit more. > > What sort of distance? Bandwidth? Error rate? > > How big is the laser and telescope? What sort of optics on the receiver? > How hard is it to point the receiver in the right direction? How hard is it > to point the transmitter telescope? ... > > How does the receiver get timing? > > -- Ilia Platone via Ferrara 54 47841 Cattolica (RN), Italy Cell +39 349 1075999 _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.