We report on the successful demonstration of second and third harmonic conversion of a high pulse energy, high average power 1030 nm diode pumped Yb-doped yttrium aluminum garnet (Yb:YAG) nanosecond pulsed laser in a large aperture lithium triborate (LBO) crystal. We demonstrated generation of 59.7 J at 10 Hz (597 W) at 515 nm (second harmonic) and of 65.0 J at 1 Hz (65 W) at 343 nm (third harmonic), with efficiencies of 66% and 68%, respectively. These results, to the best of our knowledge, represent the highest energy and power reported for frequency conversion to green and UV-A wavelengths.

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We report on the successful demonstration of a 150 J nanosecond pulsed cryogenic gas cooled, diode-pumped multi-slab Yb:YAG laser operating at 1 Hz. To the best of our knowledge, this is the highest energy ever recorded for a diode-pumped laser system.

In this paper, we present a model to predict thermal stress-induced birefringence in high energy, high repetition rate diode-pumped Yb:YAG lasers. The model calculates thermal depolarisation as a function of gain medium geometry, pump power, cooling parameters, and input polarisation state. We show that model predictions are in good agreement with experimental observations carried out on a DiPOLE 100 J, 10 Hz laser amplifier. We show that single-pass depolarisation strongly depends on input polarisation state and pumping parameters. In the absence of any depolarisation compensation scheme, depolarisation varies over a range between 5% and 40%. The strong dependence of thermal stress-induced depolarisation on input polarisation indicates that, in the case of multipass amplifiers, the use of waveplates after every pass can reduce depolarisation losses significantly. We expect that this study will assist in the design and optimisation of Yb:YAG lasers.

Memory devices having the structure of n-Si(100)/SiO 2 /metal nanocrystals(NCs)/Y 2 O 3 /Au were fabricated and their structural and electrical characteristics have been studied extensively. Gold nanoparticles were formed via laser annealing (LA) of a thin Au layer. The aim was to investigate the use of laser annealing as an effective method to produce NC-based memory devices. In particular, laser annealing was used in order to obtain uniformly spaced NCs with an average diameter of 20 nm. Best results for Au NCs were obtained using fluence below 500 mJ/cm 2 and a small number of laser pulses (1-5). After structural characterization using SEM, electrical characterization involving capacitance-voltage and current-voltage measurements revealed good (dis-)charging behavior and memory windows around 3 V. The analysis of the experimental data showed that LA is a promising annealing technique to realize devices with electrical characteristics suitable for future memory devices.