First-principles calculations of shift-current response in III–V and II–VI zincblende semiconductors

We use density functional theory to investigate the shift-current response in the zincblende semiconductors AlP, AlAs, AlSb, GaP, GaAs, InP, InAs, InSb, ZnS, ZnSe, ZnTe, CdS, CdSe, and CdTe. The objective of this study is to identify the material that exhibits the largest shift-current response under illumination and to analyze the factors governing its generation. Our results show that aluminum-based semiconductors exhibit the strongest shift-current responses, with AlSb showing the largest value of 83 µA V⁻², while CdSe shows the smallest, 14 µA V⁻². A band-resolved analysis reveals that the shift-current response in zincblende AlSb is dominated by optical transitions between the heavy- and light-hole valence bands and the first two conduction bands. We further calculated electron delocalization indices for all semiconductors considered and found that larger delocalization values correlate with higher peak magnitudes of the shift-current response. In addition, we show that hydrostatic strain does not enhance the shift current in these materials. These results indicate that AlSb is a zincblende semiconductor that efficiently generates shift current under visible-light illumination, with potential applications in optoelectronic devices.