Electronic structure calculations of delafossite Cu-based transparent conducting oxides Cu M O sub(2_)(M = B, Al Ga, In) by quasiparticle self-consistent GW approximation and Tran-Blaha's modified Becke-Johnson exchange potential

In this work, band gaps of the delafossite Cu-based transparent conducting oxides Cu M O sub(2) (M = B, Al, Ga, In) are calculated by density functional theory (DFT) implemented with many-body perturbation theory (MBPT) based on quasiparticle self-consistent GW approximation (QPscGW) and with Tran-Blaha's modified Becke-Johnson functional (DFT-TB09). Their band gaps are explicitly improved from DFT within local density approximation (LDA). Their optical absorption spectra are also calculated by solving Bethe-Salpeter equation (BSE) that includes the electron-hole correlation effect; they show strong excitonic peaks.