Intersubband energies in Al1-yInyN/Ga1-xInxN heterostructures with lattice constant close to aGaN
Artikel i vetenskaplig tidskrift, 2012
We have studied the conduction band profile and the intersubband transition energy, E-12, of Al1-yInyN/Ga1-xInxN quantum well structures. We have considered how material parameters such as non-parabolicity and the uncertainty in the bowing parameter affect E-12 and the corresponding wavelength, lambda(12). The calculations include strain and cover the transition range from telecommunication wavelengths (1.55 mu m) to the mid-infrared (similar to 10 mu m). Our results show that the transition energies of strain-free Al1-yInyN/Ga1-xInxN quantum well structures, which are lattice-matched to GaN (y = 17.7%, x = 0), resulted in wavelengths above similar to 2 mu m. To reach shorter wavelengths, we explored structures with other indium concentrations but maintaining a small mismatch to GaN. For similar to 1% lattice mismatch the wavelength lambda(12) could be reduced to less than 1.55 mu m. The results serve as a starting point for designing and epitaxial growth of photonic intersubband structures.