Modeling and Simulation of GaSb/GaAs Quantum Dot for Solar Cell

The main limitations of the conventional solar conversion device is that low energy photons cannot excite charge carriers to the conduction band, therefore do not contribute to the device's current, and high energy photons are not efficiently used due to a poor match to the energy gap. Currently, Quantum Dot Solar Cells QDSC are one of the most active research fields in the third generation solar cells which can resolve this problem. In the present work, we are interested in modeling and simulating of both standard GaAs p-i-n solar cell and GaSb/GaAs Quantum Dot Solar Cell QDSC. When comparing 40-layers GaSb/GaAs quantum dot solar cell with standard GaAs solar cell, the conversion efficiency in simulation results increased from 16.48% to 22.46%, which is relatively 36.3% increase. Also, the absorption range edge of photons with low energies extended from 900 to 1200 nm. The results reveal that the GaSb/GaAs quantum dot solar cell manifests much larger power conversion efficiency than that of p-i-n junction solar cells.