Second-harmonic generation in KB5O8· 4H2O from 217.1 to 315.0 nm

Second-harmonic generation (SHG) has been observed in KB
5
O
8
ċ 4H
2
O (KB5) between 217.1 and 315.0 nm by angle tuning in a single crystal using a single cut. A conversion efficiency of 9.2 percent was observed for type I noncritical phase matching at 217.1 nm for a peak power of 15 kW at 434.2 nm. The nonlinear coefficients d
31
and d
32
are estimated to be approximately
1.1 \times 10^{-10}
ESU (
4.0 \times 10^{-25}
m/V) and
0.08 \times 10^{-10}
ESU (
0.29 \times 10^{-25}
m/V), respectively.