Pressure dependence of elastic constants in zinc-blende GaN and InN and their influence on the pressure coefficients of the light emission in cubic InGaN/GaN quantum wells

We have studied the influence of nonlinear elastic effects on the pressure coefficients of light emission, dEE/dP, in cubic InGaN/GaN quantum wells. By means of ab-initio calculations, we have determined the pressure dependences of the elastic constants, C11, C12 and C44 in zinc-blende InN and GaN. Further, we show that the pressure dependence of the elastic constants results in significant reduction of dEE/dP in cubic InGaN/GaN quantum wells and essentially improves the agreement between experimental and theoretical values.