1. 超平坦井戸の発光像とスペクトル By
Dr. Ji-Won Oh 25 20 15 10 5 30

2. Atomic Force Microscope Image of Atomic Steps on Atomically flat (110) GaAs QW

3. Ti-Sa PL 6.8 mm GaAs AlGaAs Ti-Sa Ext.(730nm) with uniform excitation
Atomically
Flat mm
6nm
6.8 mm
GaAs
29% AlGaAs
AlGaAs mm

4. PL image & spectra (4K)
Energy transfer dynamics among islands : Any dependence on temp and density of steps in ldiff? mm

5. PL image & spectra (4K) mm

6. Longer diffusion length
At 30K t=4000 ps m=4000
By Hilmer et. al. Phys.
Rev. B (1990)
in our data
Longer diffusion length

7. PL Mission to Investigate
Point excitation of
Surface Steps :
FWHM of PL spectra from Individual
Islands and pits: Any dependence on size and steps ?
6.8 mm

8. ・Spatially Uniform point excitation beam shape : accomplished with spatial filter
But,…
・Optimization of microscopic PL experiments:
Still not resolve n+2~3 spectra and thick spectra compared to previous experiments: need to find out excitation intensity which is weak enough not to cause negative factors in PL measurements and analysis and sharp cut filter system passing spectra between 750 nm ~ 800 nm only.