Study on electronic transport and optoelectronic properties of semiconductor 2D Ge₂Y₂ (Y = As, P, N)

Several conceptual nanodevices based on the four-atom-layer α- and β-Ge₂Y₂ are constructed, and their electronic transport and photoelectronic properties are revealed by means of first-principles calculations. Our results demonstrate that the Ge₂Y₂-based p-n junction diodes show a great rectifying effect with high rectification ratio. Their p-i-n junction transistors show a field-effect behavior with better rectifying effect and stronger electronical anisotropy. Moreover, the Ge₂Y₂ monolayers have strong photoelectronic response in the visible light region, displaying excellent photoelectronic properties in the photovoltaic materials and photoelectronic transistors. Our findings uncover the multi-functional features of four-atom-layer Ge₂Y₂ monolayers, promising their extensive applications as candidates for future flexible semiconductor devices.