Designing Nanomagnet Arrays for Topological Nanowires in Silicon
Abstract
Recent interest in topological quantum computing has driven research into topological nanowires, one-dimensional quantum wires that support topological modes, including Majorana fermions. Most topological nanowire designs rely on materials with strong spin-orbit coupling, such as In As or In Sb , used in combination with superconductors. It would be advantageous to fabricate topological nanowires with Si owing to its mature technology. However, the intrinsic spin-orbit coupling in Si is weak. One approach that could circumvent this material deficiency is to rotate the electron spins with nanomagnets. Here we perform detailed simulations of realistic Si /Si Ge systems with an artificial spin-orbit gap induced by a nanomagnet array. Most of our results are generalizable to other nanomagnet-based topological nanowire designs. By studying several concrete examples, we gain insight into the effects of nanomagnet arrays, leading to design rules and guidelines. In particular, we develop a recipe for eliminating unwanted gaps that result from realistic nanomagnet designs. Finally, we present an experimentally realizable design using magnets with a single polarization.
- Publication:
-
Physical Review Applied
- Pub Date:
- November 2018
- DOI:
- 10.1103/PhysRevApplied.10.054071
- arXiv:
- arXiv:1801.03676
- Bibcode:
- 2018PhRvP..10e4071M
- Keywords:
-
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- Phys. Rev. Applied 10, 054071 (2018)