Electronic Properties of Armchair Black Phosphorene Nanoribbons Edge-Modified by Transition Elements V, Cr, and Mn

a Top and side views of a 2D phosphorene with a zoom-in view on the right-hand side. The cross-sectional views from the armchair and zigzag edges are shown below and on the left-hand side, respectively. b An APNR with TM adatoms at hollow sites (A) and top sites (B) on edge. The dashed frames indicate the size of primitive cell, and the number n denotes the width of nanoribbon. c The four magnetic configurations of APNRs. d The schematic diagram in the presence of a transverse electric fiel