Defining the optimal gradient doped Yb^(3+):YAG disk for room and low temperature diode pumped solid-state laser operations

We propose a general methodology to define the optimum doping ion volume distribution required for an efficient solid-state laser amplifier. This approach is illustrated in the context of two experimental diode pumped Yb:YAG amplifiers operating at 300 and 160 K. Processing of such tailored gain media is now possible through horizontal direct crystallization.

Overview of ytterbium based transparent ceramics for diode pumped high energy solid-state lasers

Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the recent advancement in fabricating large size laser quality transparent ceramics, diode pumped solid-state laser generating pulse energy of 100 J at 10 Hz has been recently realized at HiLASE center using Yb:YAG ceramic with Cr:YAG cladding. This review discusses Yb based high energy lasers, specific laser geometries for efficient thermal management and the role of transparent ceramics in such diode pumped high-energy-class solid-state lasers around the world.

33 W quasi-continuous-wave narrow-band sodium D_(2a) laser by sum-frequency generation in LBO

We demonstrate an all-solid quasi-continuous-wave （QCW） narrow-band source tunable to sodium D2a line at 589.159 nm. The source is based on sum-frequency mixing between lasers at 1064 nm and 1319 nm in a LBO crystal. The 1064 nm and 1319 nm lasers are produced from two diode side-pumped Nd：YAG master oscillator power amplifier （MOPA） laser systems, respectively. A 33 W output of 589 nm laser is obtained with beam quality factor M^2 = 1.25, frequency stability better than ±0.2 GHz and linewidth less than 0.44 GHz. A prototype 589 nm laser system is assembled, and a sodium laser guided star has been successfully observed in the field test.

High duty cycle,highly efficient fiber coupled 940-nm pump module for high-energy solid-state lasers

Tailored diode laser single emitters with long(6 mm) resonators and wide(1.2 mm) emission apertures that operate with940 nm emission wavelength were assembled in novel edge-cooled vertically stacked arrays, and used to construct a compact and highly efficient fiber coupled pump source for Yb:YAG pulsed high-energy class solid-state lasers. The novel configuration is shown to allow repetition rates of 200 Hz at 1 ms pulse duration, at an output power of 130 W per single emitter. The emission of two stacked arrays was then optically combined to realize pump modules that deliver6 kW peak power(pulse energy 6 J) from a 1.9 mm core diameter fiber, with wall plug efficiency of 50%. This represents a significant improvement in terms of duty cycle and electro-optical efficiency over conventional sources. The pump module has been successfully tested at the Max Born Institute, Berlin during trials for pumping of disk lasers.

High single-pulse energy passively Q-switched laser based on Y b,Gd:SrF2 crystal

We report on laser diode(LD) pumped passively Q-switched Yb,Gd:SrF2 lasers with high single-pulse energy for the first time, to the best of our knowledge. In addition, a stable Q-switched laser based on a Cr4+:Y3Al5O12 saturable absorber was demonstrated. The maximum output power of the Q-switched laser obtained was 495 m W, with a pulse width and a pulse repetition rate of 233 ns and 1.238 kHz, respectively. The corresponding single-pulse energy and the peak power were as high as 400 μJ and 1.714 k W. The laser was operated under a transverse electromagnetic mode, and the beam quality was near-diffraction-limited.