Bielefeld theorists go Karlsruhe: Challenges and chances of 4f molecules

  • date:

    Dienstag, 29.04.2025, 10:00 Uhr

  • speaker:

    Prof. Jürgen Schnack
    Universität Bielefeld

  • Abstract: In my presentation I will focus on two aspects: toroidal magnetic molecules and finite-temperature Lanczos approximations.
    Toroidal magnetic molecules are considered promising next generation building blocks for quantum storage and quantum computing at the smallest scales. One advantage would be that their toroidal texture of spins with zero net magnetic moments minimizes crosstalk in larger arrangements of such molecules. I will pre- sent the foundations of toroidal molecular spin systems, reflect on their quantum nature, and discuss the status of their applicability in terms of a theoretical modelling of bistability and coherence. The finite-temperature Lanczos method is an approximation of the partition function that allows to access thermodynamic functions also for larger spin systems with very large dimension of the Hilbert space. However, the method converges very poorly for anisotropic spin systems. I will outline recent improvements that enable us to model 3d-4f- abd 4f-based magnetic molecules as synthesized in Karlsruhe – which explains the title.