The dynamics of free carriers in polycrystalline CuIn1-xGaxSe2 (CIGS) thin films were studied using picosecond time-resolved photoluminescence (PL) and femtosecond transient-absorption (TA) measurements. The PL spectrum and the TA decay component due to the band-to-band recombination of free carriers were observed in the picosecond time region. From excitation-photon-energy-dependent TA measurements, we identified a slow intraband relaxation of free carriers in the CIGS thin films. Collectively, the combination of PL and TA experiments reveal a global feature of energy relaxation and recombination processes of free carriers in the femtosecond to nanosecond time regions.
|Physical Review B - Condensed Matter and Materials Physics
|Published - 2014 May 20
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics