[13p-PA5-1~14] 15.3 III-V-group epitaxial crystals, Fundamentals of epitaxy

[13p-PA5-3] First-Principles Study of the Band Tail States in GaPN Alloys

〇Hiroyuki Yaguchi¹ (1.Saitama Univ.)

Keywords:dilute nitride semiconductor, band tail, first-principles calculation

In GaPN alloys, up-conversion luminescence due to two-step optical absorption via band tail states is observed. The two-step optical absorption is expected to enhance the energy conversion efficiency of photovoltaic cells. In this study, the formation mechanism and properties of the band tail states in GaPN alloys have been investigated using first-principles calculations. The electronic structure, spatial distribution of electron density, and optical constants of GaPN alloys were calculated for supercells with different configurations of nitrogen atoms. It was found from the results of those calculations that local configuration of nitrogen atoms strongly affects the formation of band tail states in GaPN alloys.