Multilayer Dielectric Gratings for Petawatt-Class Laser Systems.

Britten, J. A. ; Molander, W. ; Komashko, A. M. ; Barty, C. P. J.

Technical Information Center Oak Ridge Tennessee

关键词: Dielectric gratings;    Lasers;    Multilayers;    Aspect ratio;    Dielectric materials;   

RP-ID  :  DE200415006527

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Existing Petawatt class lasers today based on Nd:glass architectures operating at nominally 500 J, 0.5 ps use meter-scale aperture, gold-overcoated master photoresist gratings to compress the amplified chirped pulse. Many lasers operating in the greater than lkJ, greater than Ips regime are in the planning stages around the world. These will require multilayer dielectric diffraction gratings to handle larger peak powers than can be accommodated with gold gratings. Models of the electric field distribution in the solid material of these gratings suggest that high aspect-ratio structures used at high incidence angles will have better laser damage resistance. New tooling for transfer etching these submicron-grating patterns and for nondestructive critical-dimension measurement of these features on meter-scale substrates will be described.