Refractive indices of MBE-grown Al_xGa_{(1−<i>x</i>)}As ternary alloys in the transparent wavelength region

A series of AlxGa(1−x)As ternary alloys were grown by molecular beam epitaxy (MBE) at the technologically relevant composition range, x &amp;lt; 0.45, and characterized using spectroscopic ellipsometry to provide accurate refractive index values in wavelength region below bandgap. Particular attention is given O-band C-band telecommunication wavelengths around 1.3 µm 1.55 µm, as well 825 nm. MBE gave a very high accuracy for layer thicknesses, alloys’ precise compositions bandgap confirmed high-resolution x-ray diffraction photoluminescence, improve model fitting accuracy. This work first systematic study MBE-grown across wide spectral range. In addition, we employed rigorous measurement-fitting procedure, which present detail.