On high-speed cross-gain modulation without pattern effects in quantum dot semiconductor optical amplifiers

摘要

In the regime with maximum linear gain in a quantum dot (QD) semiconductor optical amplifier (SOA), instantaneous gain modulation by change of the photon density is possible due to spectral hole burning effects. This, in turn, leads to the opportunity of ultrafast cross-gain modulation (XGM) without pattern effects at modulation bit-rates much higher than the interband relaxation rate. The maximum bit-rate for this pattern-effect-free XGM grows with increasing pump current density of the QD SOA.