We have investigated the effects of varying facet angle of the truncated pyramidal QDs on the strain and energy band profile. The conventional truncated QD pyramid has a height of 3 nm with the facet angle of 51˚ along with base and top width of 15 and 11 nm respectively, as observed from the previously reported transmission electron microscopy images. Also, the simulated results were validated with reported experimental data for reliability of our work. Five different angle variations viz. 41˚, 45˚, 51˚, 56˚, 61˚ were considered, referred as structure A, B, C, D and E. It is observed that the magnitude of hydrostatic strain is reduced by 1.22% for the structure E (facet angle of 61˚) and increased by 1.507% for structure A (facet angle of 41˚), when compared with the conventional structure C. Therefore, the carrier confinement would be better in case of structure E as compared to its counterparts. In comparison to structure C, the biaxial strain is 1.39% higher and 2.203% lower in case of structure E and A respectively. Higher biaxial strain would inculcate red shift in emission wavelength because of the movement of heavy-holes upward in energy, which is reflected from the computed photoluminescence peaks. The emission wavelength obtained for structures A, B, C, D and E were approximately 1140, 1151, 1155, 1161 and 1183 nm respectively. Thus, among all, structure E offered longest emission wavelength and optimum strain distribution within the heterostructure.
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