Blue light generated by frequency doubling of laser diode light in a lithium niobate channel waveguide

Blue light was generated in a LiNbO/sub 3/ channel waveguide by frequency doubling radiation from a laser diode in a guided to guided wave interaction, utilizing first-order quasi-phase-matching in a periodically domain inverted structure. A fabrication method that does not depend on the use of titanium was used. A periodic pattern of silicon oxide on the positive c-face of LiNbO/sub 3/ was used in combination with a heat treatment to achieve a periodic outdiffusion and domain reversal in the surface layer. A channel guide was subsequently formed by proton exchange.<
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