|| From PL spectrum of InGaAsN LD structures grown by MOCVD and MBE, we observe remarkable red shift of the wavelength after the addition of small concentration of nitrogen. For MOCVD growth, the concentration of nitrogen increases from 0.3% to 0.5%, and the wavelength improve from 1.17μm to 1.202μm. For MBE growth, the concentration of nitrogen increases from 2.1% to 2.6%, and the wavelength improve from 1.196μm to 1.289μm. When the concentration arrived 3%, we find the wavelength already unable to improve to long wavelength. We also observed the changes the PL peak like S-shaped from temperature-depentent PL spectrum.|
For the photocurrent and electroabsorption measurement, we prepared two the same concentration of nitrogen 2.1% samples, but different structures ,one is TR538 single quantum well structure, the other is TR515 double quantum well structure. The e1-hh1transition can be observed clear at λ=1.192 of TR515, but it was unapparent for TR538. Now, let us focus on the photocurrent and Δα signal of the fundamental e1-hh1 transitions for the largest reverse bias voltage swing(0-6v) , the maximum absorption changes of around 5394cm-1 for TR538 and 14439cm-1 for TR515. The refractive index changes of 0.019 for TR538 and 0.035 for TR515.