Luther-Davies, BarryKolev, Vesselin ZLederer, MaximilianMadsen, NathanRode, Andrei VGiesekus, JDu, K-MDuering, M.2015-12-132015-12-130947-8396http://hdl.handle.net/1885/79435We have built a mode-locked Nd : YVO4 laser with a very long resonator which produces an average power of 50 W in 13-ps pulses at 1064 nm and was designed for applications in micro-machining, the deposition of optical thin films, and the growth of nano-clusters in the laser-ablated plumes. By operating the laser at very low mode-locking repetition rates (1.5 MHz, 2.6 MHz, and 4.1MHz), high pulse power is available in a near diffraction limited beam, allowing focused intensities to exceed 1012 W/cm2 and permitting efficient evaporation of difficult materials such as Si. The high power also allows conversion into the second harmonic at 532 nm with an efficiency exceeding 80%. Measurements of the ablation mass in experiments with metals show a 30-100 times increase in the ablation rate compared to the conventional low-repetition-rate ns-range lasers.Keywords: Laser ablation; Micromachining; Nanostructured materials; Optical films; Optimization; Second harmonic generation; Superconducting materials; Thin films; Film quality; Low-repetition-rate ns-range lasers; Optical thin films; Ultrafast pulsed laser deposit20042015-12-11