Strain modulated physical properties of double perovskite Rb₂InGaCl₆ for the possible energy applications

Band gap tuning through strain engineering is a novel technique for scaling the photovoltaic efficiency of semiconductor materials. We have confirmed the stability of Rb₂InGaCl₆ using formation energies and tolerance factor and found that the mentioned material stabilizes in cubic phase. The Rb₂InGaCl₆ exhibits a semiconductor behavior with an indirect band gap of 2.12 eV. Additionally, we have applied strain to tune the electronic properties of Rb₂InGaCl₆. We find that the strain can tune the band gap and retain the semiconductor nature of Rb₂InGaCl₆. The sharp absorption peak in the optical spectra confirms the direct transition of electron from the valence band to the conduction band. Interestingly, the compressive strain induces a blue shift in optical responses and an inverse effect is observed with the tensile strain. The extended absorption from the visible region to the ultraviolet region makes it suitable for the applications in optoelectronic devices.