Regensburg 2022 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

SYSD: SKM Dissertation Prize 2022

SYSD 1: SKM Dissertation Prize

SYSD 1.2: Hauptvortrag

Montag, 5. September 2022, 10:45–11:15, H2

Nonequilibrium Transport and Dynamics in Conventional and Topological Superconducting Junctions — •Raffael L. Klees — University of Konstanz, D-78457 Konstanz, Germany

In this talk, I will give a brief overview about the main content of my dissertation. Recently, it has been shown that multiterminal superconducting junctions (MSJs) provide an ideal platform to mimic topological systems in a controlled manner [1]. In the first part, we will construct deterministic model systems of MSJs based on quantum dots that show nontrivial Andreev bound states in terms of a nonzero first and second Chern number. We will also see how the underlying object of quantum geometry and topology, the quantum geometric tensor [2], can be accessed with the help of polarized microwave spectroscopy [3]. In the second part, I will report on the theory behind recent scanning tunneling microscope (STM) experiments between single superconducting Yu-Shiba-Rusinov (YSR) bound states that form in localized magnetic impuritites on superconducting substrates [4]. Motivated by these experiments, we study YSR-functionalized STM tips and present a detailed analysis of multiple Andreev reflection processes mediated by YSR states giving rise to a very complex subgap structure in the current-voltage characteristics [5]. [1] R.-P. Riwar et al., Nat. Commun. 7, 11167 (2016). [2] M. Kolodrubetz et al., Phys. Rep. 697, 1 (2017). [3] R. L. Klees et al., Phys. Rev. Lett. 124, 197002 (2020); Phys. Rev. B 103, 014516 (2021); H. Weisbrich et al., PRX Quantum 2, 010310 (2021). [4] H. Huang et al., Nat. Phys. 16, 1227 (2020). [5] A. Villas et al., Phys. Rev. B 103, 155407 (2021).