Observation of parametric gain due to four-wave mixing in dispersion engineered GaInP photonic crystal waveguides

Abstract

We investigate four-wave mixing (FWM) in GaInP 1.5 mm long dispersion engineered photonic crystal waveguides. We demonstrate an 11 nm FWM bandwidth in the CW mode and a conversion efficiency of -24 dB in the quasi-CW mode. For picosecond pump and probe pulses, we report a 3 dB parametric gain and nearly a -5 dB conversion efficiency at watt-level peak pump powers.

Investigation of FWM in dispersion-engineered GaInP photonic crystal waveguides

“…It should be noted that, while the maximum group index achieved here is not as large as reported by other groups [13], here our TPA free material allows longer waveguides (1.3 mm) leading to comparable efficiency. Indeed, in the same waveguide we have reported gain for the first time in PhCs [36,37]. Let us notice that pump signals are not the same in both papers leading to different power ranges: in [36] coupled peak power is about 4 W, whereas it is about 250 mW in this work as the pulses are much longer; the gain regime can thus not be reached with such long pulses.…”

“…Indeed, in the same waveguide we have reported gain for the first time in PhCs [36,37]. Let us notice that pump signals are not the same in both papers leading to different power ranges: in [36] coupled peak power is about 4 W, whereas it is about 250 mW in this work as the pulses are much longer; the gain regime can thus not be reached with such long pulses.…”

Experimental GVD engineering in slow light slot photonic crystal waveguides

“…Both normal (positive) and anomalous (negative) GVD can be obtained and some SPhCWs exhibit a almost flat n g plateau over more than 20 nm bandwith. This is encouraging because state of the art nonlinear effects in integrated optics have been demonstrated in the anomalous dispersion regime and for relatively modest NDBP products 15 41 42 43 , demonstrating the important role played by the optical losses (both linear and nonlinear) that must be meticulously treated. As the proposed structures offer wavelength windows in the anomalous regime with moderate losses, they are convenient for nonlinear applications.…”

Chip-scale parametric amplifier with 11 dB gain at 1550 nm based on a slow-light GaInP photonic crystal waveguide

“…This design generates a local minimum of the group velocity dispersion corresponding to a group index of about n g 30 ( Fig. 1) and ensures significantly lower insertion losses compared to previous devices [5,[10][11][12][13], mainly at wavelengths where n g is large. Details of this design are given in [16].…”

“…GaInP PhC waveguides have indeed proven extremely efficient in various nonlinear experiments [5,[10][11][12][13] including the only demonstrations to date of parametric gain in PhC waveguides: 1.3 dB in a W1 waveguide using 32 ps pump pulses [12] and 3 dB in a dispersion-engineered waveguide where 4 W, 2 ps pump pulses were used [13].…”