Superconducting quantum networks: frustration, long-range interaction, and PT symmetry

by Prof. Ilya M. Eremin (Ruhr-University Bochum)

Wednesday 10 Dec 2025, 10:30 → 11:30 Asia/Shanghai

Tsung-Dao Lee Institute/N4F-N400 - meeting room (Tsung-Dao Lee Institute)

Host: Prof. Vadim Grinenko

Venue: TDLI Meeting Room N400

Tencent meeting link:  https://meeting.tencent.com/dm/avEevywPLawJ    

Meeting ID: 559561885, no password

 

Abstract:

Superconducting quantum circuits based on Josephson junction (JJ) arrays turned out to be excellent experimental platforms to simulate static and dynamical phenomena of quantum many-body systems. In my talk I will present some novel examples of superconducting quantum networks embedded in a dissipationless transmission line. I will concentrate on two different developments: first one refers to study JJ arrays with frustrated geometry like vertex-sharing frustrated Kagome lattice or frustrated saw-tooth chains composed of Josephson junctions. The frustration is provided by periodically arranged 0- and π- Josephson junctions. We will derive effective Ising-type spin Hamiltonian with strongly anisotropic long-range interaction and discuss quantum and classical phases of these models. In the second part of my talk, I will show how JJ arrays are used for realization of the PT-symmetric Hamiltonians and analyze novel phase transitions that occur in this case.

 

Biography:

• 2000 - 2000    Visiting scientist at the Max Planck Institute for Physics of Complex Systems in Dresden (research group Prof. Dr. Fulde, "Strong Electron Correlations")
• 2000 – 2002     Alexander von Humboldt Research Fellowship at the Institute for Theoretical Physics at Freie Universität Berlin
• 2002 - 2005    Research associate at the Institute for Theoretical Physics at the Free University of Berlin (research group Prof. F. von Oppen / Prof. K.-H. Bennemann)
• 2005 - 2010    Junior Professor (W1) at the Max Planck Institute for Physics of Complex Systems in Dresden & Technical University Carolo-Wilhelmina in Braunschweig
• 2010 - 2020    Professor (W2) at the Institute for Theoretical Physics III, Ruhr University Bochum
• 2020- Now   Chair Professor (W3) at the Institute for Theoretical Physics III, Ruhr University Bochum