Abstract

We have demonstrated highly efficient frequency doubling of femtosecond pulses in a thick, noncritically phase-matched ${\text{KNbO}}_3$ crystal under conditions of large group-velocity mismatch. At low power we observed a slope efficiency of $\sim 300\% {\text{nJ}}^{-1}$ for harmonic conversion, and at higher powers we generated 170 mW of second-harmonic blue output for 300 mW of input light. Furthermore, we have shown that the focusing dependence for our conditions of large group-velocity mismatch is considerably different from that obtained for frequency doubling of continuous-wave light. We have also demonstrated that one can tune the spectral width of the generated blue light by varying the focusing conditions.

© 1998 Optical Society of America

High-efficiency blue-light generation by frequency doubling of picosecond pulses in a thick KNbO₃ crystal

Yong-qing Li, Dorel Guzun, Greg Salamo, and Min Xiao
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Phase-matching temperature shifts in blue generation by frequency doubling of femtosecond pulses in KNbO₃

Sungkyu Yu and A. M. Weiner
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Highly efficient blue-light generation from a compact, diode-pumped femtosecond laser by use of a periodically poled KTP waveguide crystal

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Efficient type I second-harmonic generation of subpicosecond laser pulses with a series of alternating nonlinear and delay crystals

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Spectral phase correlation of coded femtosecond pulses by second-harmonic generation in thick nonlinear crystals

Z. Zheng and A. M. Weiner
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