Interaction of two avalanching layers in GaAs

The interaction between two high resistivity layers in Mn-doped GaAs, separated by typically 25 μ, can give rise to a bipolar negative resistance when the electrons produced by avalanching in one of the layers reach the other one. The electrons recombine radiatively near the non-avalanching layer. Since the layer next to the negative electrode always avalanches at a lower voltage the spatial origin of the emitted light shifts from one layer to the other, depending on the polarity of the applied voltage. © 1967.