Quantum-dot arrays as a platform for topological superconductivity

The search for a topological superconducting phase and the nonabelian Majorana states it is predicted to host is a major open challenge in condensed matter physics.

Unfortunately, problems related to material disorder have proven hard to overcome in the conventional experimental platforms based on, e.g., semiconductor nanowires or two-dimensional electron gases.

In this 4-year project, we will theoretically explore a different platform that was initially proposed by the applicant and that has now been realized in a number of breakthrough experiments within the last 1.5-years. The platform is based on a small number (down to two) connected quantum dots coupled to superconductors.

We will theoretically address questions related to the small size and strong electron-electron interactions which distinguishes this platform from more conventional realizations of topological superconductors.

This will require defining quality measures that quantify the closeness of a many-body Majorana-like state in a short quantum-dot array to a topologically protected Majorana state.

We will also propose and theoretically analyze new protocols to help experimentalists to for the first time demonstrate nonabelian quasiparticle exchange.

Finally, we will explore the possibility to use the unprecedented tunability and inherently strong interactions in the quantum-dot platform to realize even more exotic topological phases that host quasiparticles with more complex nonabelian exchange properties.