First-principle investigations of cove edged GaN nanoribbon for nanoscale resonant tunneling applications

This work investigates the impact of cove edges in gallium nitride nanoribbons (GaNNRs) as cove edges nanoribbons are energetically more stable and facilitates further tunability of electronic properties of nanoribbons. Here structural, electronic, and transport properties of cove edged GaNNRs with hydrogen (H) passivation are investigated. For this investigation, the framework of non-equilibrium Green function (NEGF) formalism based on density functional theory (DFT) has been deployed. The effect of cove edge at nitrogen (N), gallium (Ga), and at both the edges for its potential ultra-scaled device applications are studied. As compared to the pristine semiconducting nature of H–GaN–H, present DFT-based calculations of cove edged GaNNRs exhibit a metallic nature via selective H-passivation. A comparative study of binding energy (E_b) revealed that the C–GaN–H nanoribbon is structurally more stable irrespective of the width in all considered cove edged GaNNRs. Interestingly, the proposed two-terminal cove edged GaNNRs devices exhibit negative differential resistance (NDR) effect based on selective edge passivation with hydrogen atoms. The observed NDR behavior suggests that cove edged GaNNRs with selective H-passivated GaNNRs have immense potential applications for preparing nanoscale NDR devices.