Abstract
Using density functional theory, a detailed computational study is performed to explore the structural and electronic properties of a black phosphorene monolayer, bilayer, and trilayer under a uniaxial strain along the armchair (baxis) and zigzag (aaxis) directions. In the case of a monolayer black phosphorene, it is found that strain along the armchair direction slightly affects thealattice parameter and the puckering height (Delta). Along the zigzag direction, however, variation of thealattice parameter is compensated by both theaandblattice variations while the parameter Delta remains unaffected. In the case of bilayer and trilayer black phosphorene, a similar behavior is observed where the layer-spacing "d" acts as an additional degree of liberty for strain compensation. In terms of electronic properties, strain along the armchair and zigzag directions changes the nature of the Gamma point in the bandgap from a direct to an indirect electronic transition as a function of the strain value. In the strain range from -14% to +6%, all black phosphorene structures behave similarly to classical semiconductors. However, the size and strain combined effect significantly affects the Fermi energy position. Around 0% strain, all black phosphorene structures are ofp-type, while they switch to ann-typesemiconductor in the range of strain values from +2% up to +14%. This p-type to n-type transition may have a major technological impact in fields where mono- and hetero-junctions are considered.