Novel Hybrid Structures for Topological Superconductivity
Abstract
The project seeks to realize topological superconductivity at interfaces between superconductorsand topological materials. The ultimate goal is to demonstrate a clear path forward towards qubitsin planar device geometries that are robustly protected against decoherence. To achieve thisobjective, the project will develop new topological matter/superconductor combinations usingadvanced thin film synthesis techniques, especially molecular beam epitaxy, that promise to yieldlow defect densities and high-quality interfaces. A central ingredient is the ability to obtaindifferent topological phases in thin films of three-dimensional topological semimetals, such ascadmium arsenide, that possess topological surface states with high carrier mobilities and that canbe integrated into epitaxial heterostructures. Such heterostructures allow for electric field gating,integration of epitaxial superconductors and other materials needed for topological qubits, such asferromagnetic insulators. Hybrid structures will be developed and optimized through systematictuning of materials parameters in conjunction with feedback from electrical measurements. Theproject seeks to determine the specific topological matter/superconductor combinations best suitedfor topological superconductivity and, conversely, to establish the conditions, such as disorder,that serve to destabilize it. Current-phase relationships in asymmetric Josephson junctions will bea maintool for evaluating the junction characteristics. The tunability of the thin filmheterostructures synthesized in this project will be utilized for controlled experiments that canelucidate the underlying physics, test physical models and measurements, and optimizetopologicalhybrid structures towards a new generation of topological superconductors.Approved for Public Release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 05, 2021
- Source ID
- N000142112474
Entities
People
- Susanne Stemmer
Organizations
- Office of Naval Research
- United States Navy
- University of California, Santa Barbara