Title :
Optical absorption by E+ miniband of GaAs:N δ-doped superlattices
Author :
Yagi, S. ; Noguchi, So ; Hijikata, Yoshinori ; Kuboya, Shigeyuki ; Onabe, Kentaro ; Okada, Yoshitaka ; Yaguchi, H.
Author_Institution :
Grad. Sch. of Sci. & Eng., Saitama Univ., Saitama, Japan
Abstract :
The optical properties of GaAs:N δ-doped superlattices (SLs) are investigated by photoreflectance (PR), photo luminescence (PL) and photoluminescence excitation (PLE) spectroscopy. A direct evidence of the optical absorption due to an E+ related band of a GaAs:N δ-doped SLs is indicated as a clear absorption edge at 1.6 eV by PLE. AlGaAs layers fabricated on the both sides of the SL region exclude the effect of GaAs absorption on the PLE spectrum, resulting in the successful detection of the absorption property of the SL. In addition, some preliminary characterization of a solar cell using a GaAs:N δ-doped SL is shown. The photocarrier generation originating from SL miniband absorption is confirmed by quantum efficiency measurements.
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; light absorption; nitrogen; photoluminescence; photoreflectance; semiconductor superlattices; AlGaAs; E+ miniband; GaAs:N; IBSC; PLE; SL miniband absorption; electron volt energy 1.6 eV; intermediate band solar cells; optical absorption; photocarrier generation; photoluminescence excitation spectroscopy; photoreflectance; quantum efficiency measurements; semiconductor superlattices; Absorption; Gallium arsenide; Optical buffering; Optical device fabrication; Optical superlattices; Photovoltaic cells; III-V semiconductor materials; nanostructures; solar energy; spectroscopy; superlattices;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2013 IEEE 39th
Conference_Location :
Tampa, FL
DOI :
10.1109/PVSC.2013.6744981
