Although the phase noise when using optical combs to generate Rf signals is low there is no mention of the am noise.
Bruce On Tuesday, January 13, 2015 02:49:33 PM Tom Knox wrote: > I think the key to this concept is an optical comb filter. > Archita Hati of the Phase Noise measurement Group at NIST has been > researching ultra low phase noise 5MHz references using an optical standard > and comb filter as well as extensive RF components to down converting to > the desired frequency. In experiments I believe she has achieved phase > noise better then -154db @ 1Hz offset. It does appear to be the future but > currently is far to large and complex for most if any practical use. I > believe this link is the paper by Archita Hati I referred addressing > State-of-the-Art RF Signal Generation From Optical Frequency Division. > http://tf.boulder.nist.gov/general/pdf/2646.pdf > Enjoy; > Thomas Knox > > Thomas Knox > > > From: namic...@gmail.com > > Date: Wed, 14 Jan 2015 07:00:09 +1100 > > To: time-nuts@febo.com > > CC: namic...@gmail.com > > Subject: Re: [time-nuts] Current state of optical clocks and the > > definition of the second > > > > > > THe stability /accuracy of lasers is entirely dependent on the cavity > > length. Materials used are usually invar or silica, so you are no better > > off than with a quartz crystals. > > They are just a resonant cavity. > > cheers, > > Neville Michie > > _______________________________________________ > > 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. _______________________________________________ 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.
