High-efficiency 10 J diode pumped cryogenic gas cooled Yb:YAG multislab amplifier

Abstract

We report on the first demonstration of a diode-pumped, gas cooled, cryogenic multislab Yb:YAG amplifier. The performance was characterized over a temperature range from 88 to 175 K. A maximum small-signal single-pass longitudinal gain of 11.0 was measured at 88 K. When amplifying nanosecond pulses, recorded output energies were 10.1 J at 1 Hz in a four-pass extraction geometry and 6.4 J at 10 Hz in a three-pass setup, corresponding to optical to optical conversion efficiencies of 21% and 16%, respectively. To our knowledge, this represents the highest pulse energy so far obtained from a cryo-cooled Yb-laser and the highest efficiency from a multijoule diode pumped solid-state laser system.

Design of deformable mirrors for high power lasers

“…The important parameters to be estimated are: maximum required DM deformation (stroke), spatial frequency and temporal evolution of the aberrations. The aberrations can be calculated with simulations [3][4][5] using numerical models or estimated by previous experiments on similar systems [6,7] .…”

“…In the case of multi-slab amplifier [4][5][6] , the laser beam is amplified in composite slabs of active media and absorptive cladding which is present for reduction of parasitic oscillations. For example, in the case of the HiLASE laser [8] four numerical models have been developed in order to estimate the thermal effects within the gain media, optical aberrations introduced by the main multi-slab amplifier (see Figure 1) and the wavefront correction.…”

Numerical Simulation of High-Energy, Ytterbium-Doped Amplifier Tunability

“…Petawatt level, Nd:glass-based CPA systems have been demonstrated, using high-performance front-ends based e.g., in regenerative amplification in Ti:sapphire or broadband parametric amplification. Fully ytterbium-based amplification systems are limited to 10 J [7] but they already represent a very competitive option up to Joule level [8,9], making them an interesting alternative for the pre-amplifier stages of a high energy/high power Nd:glass laser, provided they can perform efficiently at the required wavelength. Recent progress towards this hybrid amplification concept has consisted in the demonstration of a Q-switched cavity based in Yb:CaF 2 extending from 1028 to 1065 nm [10], and the development of high-efficiency Yb:YAG laser oscillators operating at 1048-1050 nm [11,12], although with pulse energies limited to a few tens of nanojoules.…”

Design of a kJ-class HiLASE laser as a driver for inertial fusion energy

“…The HiLASE team is developing an Yb 3+ :YAG gain medium based concept for a 100 J/10 Hz DPSSL amplifier that could potentially be scaled to the kJ regime [5][6][7] . While there are several projects around the world that are trying to achieve the same goal [8][9][10][11] , HiLASE is expected to be completed in May 2015 and it will be the world's highest pulse energy short pulse (2-10 ns) DPSSL at 100 J and 1-10 Hz.…”