High-efficiency, high-power difference-frequency generation of 0.9–1.5 μm light in BBO

An efficient method for generation of high energy pulsed ir light
between 0.9 and 1.5 μm is described. The technique uses difference
frequency mixing of pulsed, visible dye and Nd:YAG laser light in a
10 mm long BBO crystal. Quantum efficiencies of up to 23% and ir
pulse energies up to 4.5 mJ are demonstrated. The low shot-to-shot
fluctuations of difference frequency generation in BBO make this
technique an attractive alternative to the conventional optical
parametric oscillator or Raman shifting methods that are currently
used to access this spectral region.