[20a-S011-1~8] 13.10 Compound solar cells

[20a-S011-3] Long Electron Lifetime in Intermediate States for Dot-in-Well Intermediate-Band Solar Cells

〇(D)Shigeo Asahi¹, Haruyuki Teranishi¹, Sho Watanabe¹, Daiki Watanabe¹, Toshiyuki Kaizu¹, Takashi Kita¹ (1.Kobe Univ.)

Keywords:intermediate-band solar cells,dot-in-well structure,AlGaAs

Two-step photon absorption has been investigated for realizing intermediate-band solar cells (IBSC). Recently, we have demonstrated that efficient two-step photon absorption occurs even at room temperature by using dot-in-well structure, which forms intermediate states. Besides, according to the analysis of two-step photo-excitation current for our IBSC, the excited-electron lifetime in the intermediate states was 1 ms, which is extremely long as compared to a typical lifetime in InAs quantum dots. To observe this long lifetime optically, we performed time-resolved photoluminescence for our IBSC.