Non-collinear sum-frequency generation of femtosecond pulses in a micro-structured beta-BaB2O4 crystal.

Servicio Láser, Universidad de Salamanca, Pl La Merced SN, Salamanca, Spain.
Optics Express (Impact Factor: 3.53). 11/2008; 16(22):18109-17. DOI: 10.1364/OE.16.018109
Source: PubMed

ABSTRACT Sum-frequency generation of femtosecond pulses by noncollinear phase matching in a micro-structured beta-BaB(2)O(4) crystal has been investigated. A 1D relief grating was recorded in the surface of a beta-BaB(2)O(4) crystal by direct irradiation with femtosecond pulses. Groove dimensions of 1 mum width and 200 nm depth were obtained for the recording parameters. This micro-structured crystal was used for generating ultraviolet pulses (265 nm) by noncollinear sum-frequency generation of the fundamental and the second harmonic of a Ti:Sapphire femtosecond laser system. Effective group-velocity matching between the incident pulses can be achieved for certain noncollinear processes in a compact way. The application of such device to intensity cross-correlation measurements of the second-harmonic pulse was shown.


Available from: Javier R. Vázquez de Aldana, Aug 25, 2014
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