Enhanced photoconductive response
In the figure the current distribution In (x) in the n-layer is shown for different
homogeneous generation levels at the same constant sample current I in the so called small signal regime. This
means that the current and the voltage remain in the linear part of the I-V curve and the current is small as
compared to the current where the n-layer starts to deplete. The clear trend resulting from an increase of the
generation rate g is that the current is more and more redistributed to the p-layers. Finally at highest generation
rates bipolar conduction is reached. In this special case the photoconductive response can be understood in terms of
an optically controlled gradual switching of the p-layers parallel to the n-layer. Therefore the photoconductive
response is much higher compared to the relative change of the carrier densities in the n-layer (enhanced
photoconductive response).
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