Frequency dependence in RF gain resonance by negative photocurrent resistance of electroabsorption modulator

Negative differential photocurrent resistance of the electroabsorption modulator can enhance the RF gain by inducing `resonance' in the voltage drop across the junction at very high optical power. In this paper, it is examined that the maximum RF gain value enhanced by the negative photocurrent resistance reduces as the modulation frequency is increased. For the modulator capacitance of 1 pF, as the frequency is increased from 0.5 to 1.0 and 2.0 GHz, the maximum RF gain is reduced from 21 to 15 and 9 dB, respectively.