Hatch Sabina, Wu Jiang, Sablon Kimberly, Lam Phu, Tang Mingchu, Jiang Qi, Liu Huiyun
Opt Express. 2014 May 5;22 Suppl 3:A679-85. doi: 10.1364/OE.22.00A679.
The hybrid structure of GaAs/GaAsSb quantum well (QW)/InAs quantum dots solar cells (QDSCs) is analyzed using power-dependent and temperature-dependent photoluminescence. We demonstrate that placing the GaAsSb QW beneath the QDs forms type-II characteristics that initiate at 12% Sb composition. Current density-voltage measurements demonstrate a decrease in power efficiency with increasing Sb composition. This could be attributed to increased valence band potential in the GaAsSb QW that subsequently limits hole transportation in the QD region. To reduce the confinement energy barrier, a 2 nm GaAs wall is inserted between GaAsSb QW and InAs QDs, leading to a 23% improvement in power efficiency for QDSCs.
利用功率依赖型和温度依赖型光致发光对砷化镓/砷化镓锑量子阱（QW）/砷化铟量子点太阳能电池（QDSCs）的混合结构进行了分析。我们证明，将砷化镓锑量子阱置于量子点下方会形成II型特性，该特性在锑成分达到12%时开始出现。电流密度-电压测量表明，随着锑成分的增加，功率效率会降低。这可能归因于砷化镓锑量子阱中价带势的增加，这随后限制了量子点区域中的空穴传输。为了降低限制能垒，在砷化镓锑量子阱和砷化铟量子点之间插入了一个2纳米厚的砷化镓壁，这使得量子点太阳能电池的功率效率提高了23%。
