Master's Defense: Stavros Athanasiou

Modelling of Thouless pumping in one-dimensional Josephson junction arrays

The simulation of quantum many-body systems is regarded as a demanding computational task. Both analog and digital quantum simulations provide promising solutions to tackle this computational challenge. Our study explores the analog quantum simulation of Thouless pumping in a one-dimensional Josephson junctions array (JJA). This platform is versatile and highly tunable for simulating quantum many-body phenomena.

This work explores the implementation of the Rice-Mele model, by exploiting the quantum regime of the JJA and the hardcore boson approximation. The mechanisms of quantized pumping are examined through Berryology and the Floquet theory. The effects of finite size, nonadiabaticity, and disorder on the quantized current are also discussed. 

The investigation extends to studying pumping in the presence of external superconducting leads. Our results demonstrate that transport is quantized when the winding of the many-body quasienergy over the Floquet-Brillouin zone is nontrivial, as the superconducting phase difference varies. In this talk, we summarize our core findings, which contribute to understanding topological quantum pumping in Josephson junctions arrays, highlighting the potential of performing analog quantum simulation of transport phenomena in this platform.