Study on structural and optical properties of α-(Al<italic>x</italic>Cr<italic>1-x</italic>)2O3 (0 ≤ <italic>x</italic> ≤ 1) solid solutions.

We report on structural and optical properties for ternary α-(Al<italic>x</italic>Cr1-<italic>x</italic>)2O3 (0 ≤ <italic>x</italic> ≤ 1) solid solutions synthesized by using solid sate reaction method. Single R-3c phase was obtained for the Aluminum composition of 0 ≤ <italic>x</italic> ≤ 1. Due to difference in the ionic radia of Al3+ and Cr3+, in plane lattice parameter showed deviation from the vegard’s law. Optical absorption spectra for the solid solutions showed a blue shift of ∼ 0.5 eV in the optical gap. It has also been observed that Cr 3d level shifted towards the O 2p level in the valance band which indicates the enhancement of hybridization in the d and p levels, which is related to the delocalization of hole states, responsible for p-type conduction in wide band gap semiconductors. The results suggests that ternary α-(Al<italic>x</italic>Cr1-<italic>x</italic>)2O3 (0 ≤ <italic>x</italic> ≤ 1) can be useful in the field of UV transparent electronics and UV photodetectors. [ABSTRACT FROM AUTHOR]