Optimizing surface defects for atomic-scale electronics: Si dangling bonds

Abstract

Surface defects created and probed with scanning tunneling microscopes are a promising platform for atomic-scale electronics and quantum information technology applications. Using first-principles calculations we demonstrate how to engineer dangling bond (DB) defects on hydrogenated Si(100) surfaces, which give rise to isolated impurity states that can be used in atomic-scale devices. In particular we show that sample thickness and biaxial strain can serve as control parameters to design the electronic properties of DB defects. While in thick Si samples the neutral DB state is resonant with bulk valence bands, ultrathin samples (1-2 nm) lead to an isolated impurity state in the gap; similar behavior is seen for DB pairs and DB wires. Strain further isolates the DB from the valence band, with the response to strain heavily dependent on sample thickness. These findings suggest new methods for tuning the properties of defects on surfaces for electronic and quantum information applications. Finally, we present a consistent and unifying interpretation of many results presented in the literature for DB defects on hydrogenated silicon surfaces, rationalizing apparent discrepancies between different experiments and simulations.

8 pages, 4 figures. Includes 11 pages supplemental material

References in corpus (13)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Self-consistent hybrid functional for condensed systems
• Room temperature quantum bit storage exceeding 39 minutes using ionized donors in 28-silicon
• Quantum Simulation of the Hubbard Model with Dopant Atoms in Silicon
• Theoretical study of isolated dangling bonds, dangling bond wires and dangling bond clusters on H:Si(100)-(2$\times$1) surface
• Scanning tunneling spectroscopy reveals a silicon dangling bond charge state transition
• Time-Resolved Imaging of Negative Differential Resistance on the Atomic Scale
• Energetics and stability of dangling-bond silicon wires on H passivated Si(100)
• Spin relaxation and donor-acceptor recombination of Se${}^{+}$ in 28-silicon
• Importance of bulk states for the electronic structure of semiconductor surfaces: implications for finite slabs
• Search for a Metallic Dangling-Bond Wire on $n$-doped H-passivated Semiconductor Surfaces
• Spin transport in dangling-bond wires on doped H-passivated Si(100)
• Controlled Coupling and Occupation of Silicon Atomic Quantum Dots

Cited by in corpus (7)

• Binary Atomic Silicon Logic
• SiQAD: A Design and Simulation Tool for Atomic Silicon Quantum Dot Circuits
• Ionic Charge Distributions in Silicon Atomic Wires
• Dangling bonds on the Cl- and Br-terminated Si(100) surfaces
• Qubit guidelines for solid-state spin defects
• Hydrogen inserted into the Si(100)-2x1-H surface: A first-principles study
• Giant, anomalous piezo-impedance of silicon-on-insulator