Low-symmetry nanowire cross-sections for enhanced Dresselhaus spin-orbit interaction
| Autor: | Dominik M. Zumbühl, Daniel Loss, Miguel J. Carballido, Christoph Kloeffel |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Physics
Coupling Central angle Condensed matter physics Condensed Matter - Mesoscale and Nanoscale Physics Condensed Matter::Other Nanowire FOS: Physical sciences 02 engineering and technology Spin–orbit interaction Electron Circular sector 021001 nanoscience & nanotechnology Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 01 natural sciences Condensed Matter::Materials Science Lattice (order) Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences 010306 general physics 0210 nano-technology Low symmetry |
| Popis: | We study theoretically the spin-orbit interaction of low-energy electrons in semiconducting nanowires with a zinc-blende lattice. The effective Dresselhaus term is derived for various growth directions, including -oriented nanowires. While a specific configuration exists where the Dresselhaus spin-orbit coupling is suppressed even at confinement potentials of low symmetry, many configurations allow for a strong Dresselhaus coupling. In particular, we discuss qualitative and quantitative results for nanowire cross-sections modeled after sectors of rings or circles. The parameter dependence is analyzed in detail, enabling predictions for a large variety of setups. For example, we gain insight into the spin-orbit coupling in recently fabricated GaAs-InAs nanomembrane-nanowire structures. By combining the effective Dresselhaus and Rashba terms, we find that such structures are promising platforms for applications where an electrically controllable spin-orbit interaction is needed. If the nanowire cross-section is scaled down and InAs replaced by InSb, remarkably high Dresselhaus-based spin-orbit energies of the order of millielectronvolt are expected. A Rashba term that is similar to the effective Dresselhaus term can be induced via electric gates, providing means to switch the spin-orbit interaction on and off. By varying the central angle of the circular sector, we find, among other things, that particularly strong Dresselhaus couplings are possible when nanowire cross-sections resemble half-disks. 17 pages containing 7 figures as PDF-files |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|