[16a-A304-1~8] 13.9 Compound solar cells

[16a-A304-1] Excitation Power Dependence of the Photoluminescence Spectra of InGaAs/GaAsP Wire on Well structures

〇Tetsuo Ikari¹, Yamamoto Naoki¹, Komaba Shintaro¹, Sugiyama Masakazu², Fukuyama Atsuhiko¹ (1.Univ Miyazaki, 2.Univ Tokyo)

Keywords:Quantum structure solar cell, electronic band structure, optical properties

We developed a new design as wire-on-well (WoW) based on the InGaAs/GaAs/GaAsP superlattice (SL) device fabrication technology. When the SL was grown on a slightly tilted substrate, 6° toward [111] from the GaAs (001) plane, periodically aligned InGaAs nano-wires on planer wells were formed. Photoluminescence (PL) and photoreflectance (PR) measurements were carried out to understand the carrier dynamics in this structure. We then observed the transition from e1 to hh1 quantized levels in the PL and PR spectra. The observed PL peak showed the blueshift when the excitation power increased. We considered that carrier redistribution occurred when the number of the photo-excited carrier increased. The electrons began accumulating in the smaller well-width region of higher quantum energy levels. Then, the PL peak shifted to the higher energy region.