SPICE Workshop on Hybrid Correlated States and Dynamics in Quantum Materials, May 14th - 16th 2024
Wolfgang Belzig
Superconductivity is the basis of practically all modern quantum coherent phenomena in many-body solid state systems. Due to the activation of quantum mechanical phases as degrees of freedom in superconducting multi-terminal structures, effects lie topological quantum bits, Weyl physics and macroscopically quantized phenomena become possible.
In my talk, I will discuss novel possibilities to realize complex, topological nontrivial states of matter in superconducting complex structures. Examples are Berry spectroscopy of Weyl-Andreev nodes in synthetic dimensions [1], fractional states of matter of Cooper pair networks [2], high-dimensional topology such as the Second Chern number accompanied by a non-Abelian Berry phase [3]. First experimental steps towards realizing such highly non-trivial quantum effects will be discussed and accompanied by concrete theoretical predictions for experimentally observables like tunnel spectroscopy, supercurrent and quantized responses.
[1] R. L. Klees, G. Rastelli, J. C. Cuevas, and W. Belzig, Microwave Spectroscopy Reveals the Quantum Geometric Tensor of Topological Josephson Matter, Phys Rev Lett 124, 197002 (2020).
[2] H. Weisbrich, R. L. Klees, O. Zilberberg, and W. Belzig, Fractional Transconductance via Non-Adiabatic Topological Cooper Pair Pumping, arxiv: 2212.11757 (2022).
[3] H. Weisbrich, R.L. Klees, G. Rastelli, and W. Belzig, Second Chern Number and Non-Abelian Berry Phase in Topological Superconducting Systems, PRX Quantum 2, 010310 (2021)