Single mode lasing by current injection in T-shaped QWRs
Sample No. 8-4-05.2#2C
By Shu-man Liu
2006/4/8
Structure and composition
IL at different temperatures
Fig.1 I-L curves recorded with increasing current
Fig.2 I-L curves recorded when decreasing currentInset: Threshold current anddifferential quantum efficiency vs.temperature
IV Curves at different temperatures
The derivative of the voltage versus injection Current characteristic curve shows a high and bad dynamic series resistance at 5K.
Lasing spectrum at 40K
EL spectrum at 5K
With increasing injection current, a new EL peak at high energyappears, which is attributed to emission from doped layer compared with microEL and EL imaging results.
Lasing peak energy vs. T
The lasing peak red-shifts with increasing temperature. The solid line in Fig.(b) represents the temperature dependenceof GaAs band-gap energy which wasshifted to fit the QWR peak energies.
Thus, the red-shift is due to the band-gapshrink of GaAs with increasing temperature.
Lasing mode hopping
The mechanism of modeis not understand.