15:00 〜 15:15
▲ [19p-C309-4] Size Optimization of InAs Quantum Well Islands for Photon Upconversion Applications
キーワード：InAs, Upconversion, Quantum Well Islands
Disk-like InAs Quantum well islands (QWIs) have been shown to exhibit efficient photon upconversion and is one of the candidate systems for intermediate-band solar cell (IBSC) applications. In this report, the size dependence of the upconversion efficiency of QWI is investigated by photoluminescence measurements. By using a sample with a thickness gradient in the InAs layer and therefore varying sizes of QWIs, it was found that the upconversion efficiency increases with the decreasing size of the QWIs, with a peak upconversion efficiency of ~0.1%. Furthermore, the power dependence of the upconversion intensity showed a superlinear trend, which agrees with previous reports. These results give insight to the size dependence of the upconversion process in QWIs.