Single-layer GaInO3: Promising material for optoelectronic and out-of-plane piezoelectric devices

Two-dimensional (2D) semiconductors with intrinsic dipole show glorious prospects in the fields of nanoelectronics. Herein, the possible applications of single-layer GaInO3 in the realms of optoelectronics and piezoelectricity are investigated via the first-principles study. We find that single-layer GaInO3 exhibits a large vertical dipole moment and a direct bandgap (1.53 eV). Its transport mobility for electrons and holes both surpasses 2000 cm2·V−1·s−1. The effective separation of charge carriers for single-layer GaInO3 is confirmed by the strong inside electric field and the spatially isolated conduction band minimum (CBM) and valence band maximum (VBM). The allowed optical transition makes single-layer GaInO3 a hopeful candidate for optical absorbers and detectors. Finally, we also find that single-layer GaInO3 holds a prominently stronger out-of-plane piezoelectric effect than that of previous 2D materials and will play a big role in modern top-bottom gate technologies. In summary, this work proves that single-layer GaInO3 is a promising candidate for atomic-thick optoelectronic and piezoelectric devices.