Single mode lasing by current injection in T-shaped QWRs

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.