Investigation of the total conductivity of heterolasers with a strip contact with reverse bias

Abstract

The electrical properties of DGS lasers with a strip contact on the basis of Al_xGa_1−xAs with reverse bias, including the breakdown domain, are investigated experimentally. It is shown that the dependence of the barrier capacitance on the voltage is described well by the relationship C_b = C_o/(1− V/V_k)^1/m, where C_o = (50–110) pF and m = 2.0–2.7. The capacitance for zero bias C_o depends weakly on the frequency in the range 660 kHz–60 MHz. The active conductivity for V = 0 increases by approximately an order as the frequency changes from 15–60 MHz. The dependence of the active and reactive components of the total laser conductivity on the current is investigated at fixed frequencies in the range mentioned. The weak dependence of the reactive component on the current is noted in the breakdown regime associated with stabilization of the reverse voltage on the laser. Possible physical mechanisms responsible for the kind of characteristics obtained are discussed.