Abstract
We show theoretically and experimentally that enhancements of up to 40 dB in the efficiency of optical transmission of microwave signals can be obtained by using a single quantum well laser transmitter whose contact is segmented into two sections, and modulation is applied to one of the sections. The improvement is dependent fundamentally on the relaxation oscillation frequency of the device, with the improvement factor dropping to around 15 dB at relaxation oscillation frequencies approaching 10 GHz.