Abstract

In spite of the large nonlinearity, a disadvantage of periodically poled LiNbO₃ (PPLN) is that the bandwidths for quadratic interactions are quite narrow, limiting its broad band applications and those with ultra fast pulses. The most direct way to broaden the bandwidth (Δλ) is to reduce the interaction length (l) because Δλ ∝l. On the contrary, the efficiency of frequency conversion η ∝ l⁻², resulting in a poor trade-off between the bandwidth and the conversion efficiency.

© 2002 Optical Society of America