Experimental observation of quantum-limited timing jitter in an active, harmonically modelocked fiber laser

Summary form only given. Recent measurements of timing jitter in actively modelocked fiber lasers (AMFLs) producing picosecond pulses at GHz rates have demonstrated performance limited by the local oscillator (LO) driving the laser. This is a technological limit and does not reveal the fundamental timing jitter. The fundamental jitter is determined by the ASE noise power and a set of characteristic coefficients determined by the laser parameters. By using an ultralow phase-noise LO and a sensitive residual phase noise measurement, we have observed quantum-limited timing jitter of an AMFL and compared the jitter to a theoretical model derived analytically from the master equation of modelocking.