Page 194 - High Power Laser Handbook

CHAPTER 7

Introduction to

High-Power

Solid-State

Lasers

Gregory D. Goodno
Senior Scientist, Northrop Grumman Aerospace Systems,
Redondo Beach, California

Hagop Injeyan
Technical Fellow, Northrop Grumman Aerospace Systems,
Redondo Beach, California

7.1 Introduction
Recent years have witnessed rapid growth in both average and peak
powers attainable from solid-state lasers (SSLs). Continuous SSL out-
1
put powers with good beam quality have reached the 100-kW level,
and SSL pulse energies and peak powers have exceeded 1 MJ and 1
PW, respectively. This progress has been the result of many years of
2,3
iterative advances in materials and processing methods, coupled
with revolutionary developments, such as diode-pumping, thermally
scalable laser architectures, and wavefront correction techniques.
Solid-state lasers differ from gas or chemical lasers in several
important respects. First, as the name suggests, the lasing material is
solid phase and thus cannot be flowed during operation. Volumetri-
cally deposited waste heat must be removed from the surfaces, typi-
cally leading to large thermal gradients during high-average-power
(HAP) operation. Second, all SSLs are optically pumped. Hence, a
key engineering consideration is selection of the optical pump source

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