Indexed on: 30 Jul '02Published on: 30 Jul '02Published in: Physical review letters
A first-principles-derived scheme is developed to compute the piezoelectric coefficients e(i j) of semiconductor alloys. This method is applied to study the effect of atomic arrangement and composition on e(33 ) in wurtzite Ga (1- x)In xN. Results obtained by this method for ordered structures are in good agreement with direct first-principles calculations. We predict that atomic ordering can have a large effect on piezoelectricity and that e(33 ) of disordered materials is nearly linear with composition. Microscopic origins for these features are revealed.