Quantum dot intermediate band solar cell material systems with negligible valence band offsets

In this paper, material triads (quantum-dot/barrier/substrate) are presented that may implement quantum dot intermediate band solar cells with conversion efficiencies greater than 60%. Triads whose barrier material and substrate material are lattice-matched are presented. In addition, triads are presented with the lattice constant of the substrate in-between the lattice constant of the barrier and the lattice constant of the quantum dot. The latter case provides triads that may remove strain during epitaxial growth.