Abstract

Generation of high-power and high-reproducibility ultra-short laser pulses is demanded by a wide range of applications such as materials processing, medicine and optical spectroscopy. Passive mode-locking of CW-pumped lasers is the conventional and most robust approach for obtaining steady-state laser operation but their single-pulse energy and average power are quite limited e.g. to ~100 W at 80-110 MHz repetition rate. Although the Yb³⁺-based thin-disk laser oscillators can operate with ~1-kW output power in CW mode, mode-locking is demonstrated up to ~275 W at repetition rate of 16 MHz [1]. In addition, this method for generation a train of ps-pulses requires a high degree of system complexity and development of passive mode-locking techniques applicable to oscillator with high average power. An alternative approach to meet the application requirements of ps-pulses with high-energy and average power is to generate a burst of picoseconds pulses with a kilohertz repetition rate and controllable duration and energy. Besides, such time structure is shown to be effective for a broad area of applications based on laser material interaction [2].

© 2013 IEEE