Bachelor's Thesis

Dielectric Response of a Superconductor Near Percolation

Superconductivity, Percolation, Microwave Spectroscopy, Criticality

Keywords

Superconductivity, Percolation, Microwave Spectroscopy, Criticality

 

Successively connecting isolated, conducting, microscopic islands eventually leads to percolation with macroscopic conduction. The macroscopically insulating state close to such an insulator-conductor transition can be strongly polarized and should exhibit a divergence of the dielectric constant when approaching this transition. In this project, we want to study this diverging dielectric constant near percolation for the case of a superconductor, namely Sn. We will use cryogenic microwave coplanar resonators as probes, which are covered with island-structured non-percolated Sn films, and we will study their dielectric response above and below the superconducting transition temperature.

 (c) Atomic force microscope (AFM) images of Sn thin films below and above percolation.  (M. Beutel et al., Supercond. Sci. Technol. 29, 085011 (2016).)
 (c) Divergence of dielectric constant near percolation for Au at room temperature.  (M. Hoevel et al., Phys. Rev. B 81, 035402 (2010).)
Marc Scheffler
Dr.

Marc Scheffler

Head of the Microwave Lab

Martin Dressel
Prof. Dr. rer. nat.

Martin Dressel

Head of Institute

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