Efficiency Limit of Intermediate Band AlxGa1-xAs Solar Cell Based on   AlyGa1-ySb Type-II Quantum Dots Embedded Outside of the Depletion Region
  The intermediate band (IB) cell is a concept of highly efficient solar cells proposed by Luque and Marti in 1997. The IB concept uses nonlinear effect of two photon absorption enforced with concentration of such photons for generation of additional photocurrent in single p-n-junction cells. In this theoretical work we demonstrate an important role of self-organized strained type-II AlyGa1-ySb quantum dots for operation in IB GaAs solar cells. 
A. Kechiantz, A. Afanasev, J.-L. Lazzari
cond-mat.mes-hall cond-mat.mtrl-sci