Ultrashort Laser Pulse Phenomena, 2nd Edition

370 Ultrashort Sources II: Examples

when pumped with InGaAs diode lasers at 942 nm. A small quantum defect

implies that a minimum amount of energy is dissipated in the crystal in the form

of heat.

The combination of diode pumping (high wall plug efficiency), broad band-

width and small quantum defect has spurred the development of short pulse, high

average power Yb:YAG sources. The main problem to be overcome in develop-

ing high average output power sources is the removal of the heat produced by

pump intensities of the order of tens of kW/cm

2

. Two solutions have been imple-

mented, which led to pulse sources at 1.03 µm, subpicosecond pulse duration,

and several tens of watts of average power:

1. A thin disk Yb:YAG laser [114] and

2. Laser rods with