Insight into the Stacking Effect on Shifted Moiré Patterns of Bilayer Phosphorene: A comprehensive First-principles Study

A deeper understanding of the role of interlayer interaction in controlling the structural and electronic properties of twisted bilayer phosphorene is very crucial. We employed a first-principles approach, to comprehensively study bilayer phosphorene through relative translation along different directions to reveal a direct correlation between the potential energy surface and the interlayer equilibrium distance. The high symmetric moiré patterns with the most stable, metastable, and transition states were found associated with AB, Aδ, and TS stacking configurations, respectively. The transition state (TS) configuration between the AB and Adelta configurations was found with an energy barrier of ∼1.253 meV/atom. The character of the electronic bandgap with respect to shifting shows an anisotropic behavior ranging between 0.62 – 1.22 eV with transitions from indirect to direct bandgap nature under shifting, implying a tunable bandgap by stacking engineering. Orbital hybridization at the interfacial region induces a redistribution of the net charge (∼0.002 – 0.01e) leading to a strong polarization with stripe-like electron depletion near the out-of-plane lone pairs and accumulation in the middle of the interfacial region. It is expected that such interesting findings will make moiré patterns of shifted bilayer phosphorene promising as a versatile shiftronics material for nanoelectronics applications.