Superconducting phenomena in Fibonacci quasicrystals
Oladunjoye Awoga
Lund University, Sweden
Recent studies have demonstrated that quasiperiodicity enhances proximity-induced superconductivity and its effects. Quasicrystals exhibit multiple nontrivial electronic properties, such as topological winding states, multifractal structures, and critical states. These properties are likely to influence superconductivity. Advances in atom-by-atom deposition on superconductors, as seen in scanning tunneling microscope experiments, allow for the creation of artificial superconducting quasicrystals. In this talk, I will present our study on topological superconductivity in Fibonacci chains, a one-dimensional quasiperiodic arrangement of atoms. Our results show a competition between an enlarged topological superconducting phase induced by the quasicrystal structure and the intrinsic quasicrystal phase. Additionally, I will demonstrate that a Josephson junction connected via a Fibonacci chain weak link exhibits multiple nontrivial features in the Josephson current. Also, I will illustrate how the critical current can measure the quasicrystal topological invariant, specifically the gap label. Finally, I will present some outlook.
References:
1. A. Jagannathan, Rev. Mod. Phys. 93(4) 045001 (2021)
2. A. Kobialka, O. A. et. al, arXiv:2405.12178
3. A. Sandberg, O. A. et. al, arXiv:2405.05660