Noncollinear quasi-phase matching, in combination with spectral angular dispersion, can be used to broaden the bandwidth of second-harmonic generation (SHG) beyond the bandwidth for collinear, nondispersed interactions. A general theoretical treatment is presented, in addition to a solution that predicts the generated field for the case of a Gaussian input field; a comparison is made between this technique and others available for broadband SHG. An experiment in periodically poled lithium niobate demonstrates SHG of a 138 fs pulse at 1550 nm in a 1 cm length crystal (with a collinear acceptance bandwidth 13 times narrower than the first-harmonic bandwidth) with minimal spectral narrowing.
© 2005 Optical Society of America
Andrew M. Schober, Mathieu Charbonneau-Lefort, and Martin M. Fejer, "Broadband quasi-phase-matched second-harmonic generation of ultrashort optical pulses with spectral angular dispersion," J. Opt. Soc. Am. B 22, 1699-1713 (2005)