Liquid-cooled Nd:phosphate split-slab large aperture amplifier pumped by flash-lamps. (August 2022)

• Record Type: Journal Article
• Authors: Lupi, Jean-François; Dalbies, Pierre-Marie; Cavaro, Sandy; Manac'h, Patrick; Bordenave, Edouard; Sajer, Jean-Michel; Moreau, Julien G.; Blanchot, Nathalie; Neauport, Jérôme
• Is Part Of: Optics & laser technology. Volume 152(2022)
• Publication Date: 2022-08
• Subjects: Laser cooling -- Thermal effects -- Neodymium; 78A60; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2022.108101
• Languages: English
• ISSNs: 0030-3992

Abstract

Graphical abstract: Highlights: A liquid cooled Nd:phosphate split-slab 90 × 90 mm 2 aperture amplifier cell was built. Stable gain and low wavefront distortions are evidenced over a 1 shot/min repetition rate. Thermo-optical-mechanical-fluidic multi-physics modeling predicts these results. Abstract: High power laser facilities have been developed to achieve novel standards in light-matter interactions. The repetition rate is severely limited by the heating of the large size components, and in particular the large-aperture amplifiers. Cooling these optical components turns out to be a major challenge for increasing the repetition rate of high power laser beam lines. Here we report a practical implementation of a large aperture Nd:phosphate split-slab based amplifier using a liquid cooling system. The amplification of a 90 × 90 mm 2 beam with a gain coefficient of 1.135 per pass and wave-front deformation lower than λ /3 per pass is achieved with a repetition rate of 1 shot per minute. The cooling system is sufficient to maintain the gain as well as the beam quality over a long time operation. Additionally, the pressure inside the amplifier can be controlled to minimize the optical deformation. This single liquid-cooled amplifier is a promising step towards future beam-lines able to deliver hundreds of shots per day with beam quality compatible with target focusing applications.