Measurement of modulation saturation intensity in strain-balanced, undefected InGaAs/GaAsP modulators operating at 1.064 μm

Abstract

We measure high modulation saturation intensities in both strain‐relaxed InGaAs/GaAs multiple‐quantum‐well (MQW) modulators (107 kW/cm²) and strain‐balanced InGaAs/GaAsP MQW modulators (31 kW/cm²) operating at 1.064 μm, measured with a Nd:YAG laser. This compares with 16 kW/cm² for GaAs/Al_0.3Ga_0.7As thin barrier MQW modulators and 65 kW/cm² for GaAs/Al_0.02Ga_0.98As shallow MQW modulators operating near 850 nm (reflection modulators). The advantage of the strain‐balanced system is that it results in an undefected material with sharper excitonic features and better morphology compared to the strain‐relaxed system. This study shows that the InGaAs/GaAsP system may be used to obtain long wavelength operation with these advantages without incurring an unreasonable penalty for high power operation due to the higher barriers.