Experimental investigation of inhomogeneously pumped injection lasers

An investigation was made of inhomogeneously pumped injection lasers in the form of Al_xGa_1-xAs–GaAs double heterostnictures. Bistable operation of such lasers was demonstrated and the switching time between the two states was less than 2×10^–10 sec. A study was made of regular pulsations of the output radiation resulting from inhomogeneous pumping. The pulsation frequency was tunable up to 2 GHz and the duration of each pulsation (spike) was less than 2.5×10^–10 sec. It was found that the pulsation frequency obeyed f~(I – I_th)^1/2, where I and I_th are the current through the heterodiode and the threshold value of this current, respectively.