Elimination of transient vertical-cavity surface-emitting laser oscillations using photoactive feedback

It is demonstrated numerically that photoactive layers placed in a vertical-cavity surface-emitting laser (VCSEL) cavity eliminate the generic transient oscillations caused by the increasing rate of carrier depletion with increasing photon flux ∂(dN/dt)/∂P<0. Reversing the sign ∂(dN/dt)/∂P>0, using appropriately chosen photoactive layers, makes the cavity relaxation frequency purely imaginary; the laser asymptotes to steady state without modulation as an overdamped oscillator. The sign reversal depends mainly on the layer doping parameters, but not on the laser power, thus suppression holds over the laser operation range.