Superconductivity

The theory of Bardeen, Cooper and Schrieffer (BCS) provides a basic description of conventional superconductivity mediated by quantized lattice vibrations, or phonons. However, many other different forms of superconductivity have been discovered, which require new concepts and models. To increase the understanding of novel forms of superconductivity, we both develop theoretical methods and perform large-scale self-consistent calculations. We are primarily interested in the mechanisms and properties of unconventional, topological, and inhomogeneous superconductivity, as well as functionality of superconducting devices and hybrid structures, where superconductivity can be combined with other exotic phases of matter.

We primarily use low-energy effective models to study superconductivity in many different novel materials and in superconducting hybrid structures. Current interests range from high temperature cuprate superconductivity and topological superconductivity with Majorana fermions, to superconductivity in twisted bilayer graphene and other moiré systems or flat band systems. Other areas of interest are odd-frequency superconductivity, superconducting phase crystals, non-Hermitian effects, and superconductivity in non-crystalline materials, including disordered systems and quasicrystals.