Na. Shapiro et al., Dependence of the luminescence energy in InGaN quantum-well structures on applied biaxial strain, PHYS REV B, 62(24), 2000, pp. R16318-R16321
Direct application of biaxial strain to GaN and InGaN/GaN multiple quantum-
well (MQW) structures is achieved through the use of a specially designed p
ressure cell. The photoluminescence of the samples is measured as a functio
n of the applied biaxial strain. The luminescence of the GaN sample redshif
ts with tensile strain in a manner that agrees quantitatively with the expe
cted shrinkage of the energy gap. The luminescence of the InGaN MQW structu
res shows a smaller than expected redshift for one sample, and a blueshift
for another. This blueshift agrees with calculations based on the built-in
electric field and the piezoelectric effect in a quantum well in which the
radiative recombination is dominated by the quantum-confined Stark effect.