  We investigated the current-voltage characteristic of InAs/GaAs quantum dot
intermediate band solar cells (QD IBSCs) with different n-type doping density
in the QD layer. The n-type doping evidently increases the open circuit
voltage, meanwhile decreases the short circuit current density, and leads to
the conversion efficiency approaching that of the control solar cell, that is
the major role of n-type doping is to suppress the effects of QDs on the
current-voltage characteristic. Our model adopts practical parameters for
simulation rather than those from detailed balanced method, so that the results
in our simulation are not overestimated.
