CONSEQUENCES OF CONTROLLING RADIATIVE LOSS IN QUANTUM WELL SOLAR CELLS

摘要

The use of quantum wells in photovoltaic devices are often discussed in terms of providing additionalcurrent to improve the efficiency of multi-junction photovoltaic devices. However, quantum wells also provide somefreedom to manipulate the radiative recombination in the quantum well solar cell. Under concentrated sunlight, thequantum well solar cell becomes radiatively limited, so the voltage of the quantum well solar cell becomes dependentupon the radiative loss from the device, which in turn can be controlled by careful design of the solar cell.Anisotropic radiative recombination from a quantum well solar cell leads to a small voltage improvement in the solarcell since the recombination current is suppressed in directions where sunlight is not absorbed. Further, we show thatstrong radiative coupling between sub-cells takes place, resulting in a multi-junction solar cell that is tolerant to dailyand seasonal changes to the solar spectrum.