Novel concept of sub-picosecond timing system and its applications in fundamental metrology

We are presenting a novel concept of the time interval measurement which uses a surface acoustic wave (SAW) filter as a time interpolator. Based on our previous results we have designed and constructed a timing device which allows registration of times of arrival of pulses with a single shot precision of 800 fs RMS, the time interpolation nonlinearity bellow 200 fs, and the stability in sense of TDEV <10 fs for averaging times from 300 s to 3000 s. Two identical timing devices above have been used in an experiment, in which the frequency outputs of two Hydrogen masers were compared. The experiment proofed that one of possible applications of the timing device is a comparison of high performance low-noise frequency sources and measurement of their frequency stability in the time-domain. The noise background of the timing system was negligible for averaging intervals on the order of 100 ms and longer.