Attosecond-precision ultrafast photonics

We review our recent progress toward attosecond-precision ultrafast photonics based on ultra-low timing jitter optical pulse trains from mode-locked lasers. In femtosecond mode-locked lasers, the concentration of a large number of photons in an extremely short pulse duration enables the scaling of timing jitter into the attosecond regime. To characterize such jitter levels, we developed new attosecond-resolution measurement techniques and show that standard fiber lasers can achieve sub-fs high-frequency jitter. By leveraging the ultra-low jitter of free-running mode-locked lasers, we pursued high-precision optical-optical and optical-microwave synchronization techniques. Optical signals spanning 1.5 octaves were synthesized by attosecond-precision timing and phase synchronization of two independent mode-locked lasers. High-stability microwave signals were also synthesized from mode-locked lasers with drift-free sub-10-fs precision. We further demonstrated the attosecond-precision distribution of optical pulse trains to remote locations via timing-stabilized fiber links. Finally, the application of optical pulse trains for high-resolution sampling and analog-to-digital conversion is discussed. [GRAPHICS] The ultra-low timing jitter of optical pulse trains from femtosecond mode-locked lasers can be used for the attosecond-precision generation, distribution, measurement, and synchronization of optical and microwave signals. (C) 2010 by WILEY-VCH Verlag GmbH & Co. KGaA. Weinheim