Abstract

The intermediate band (IB) solar cell is meant to convert sub-bandgap photons into current. For it a permitted energy band for electrons is formed within the forbidden bandgap; in this way two sub-bandgap photons can pump one electron form the valence band (VB) to the conduction band (CB) using the IB as stepping stone. Quantum dot (QD) confined states can provide the IB energy levels. Thanks to the separation of the Fermi level into three quasi Fermi levels (QFLs) it can do so at a voltage limited by the bandgap. The IB-CB QFL splitting is only produced in present solar cells at low temperatures. This topic will not be discussed in this lecture.

© 2011 Optical Society of America