SKM 2023 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 33: Many-Body Quantum Dynamics (joint session DY/TT)

TT 33.12: Vortrag

Mittwoch, 29. März 2023, 12:45–13:00, MOL 213

Simulating infinite temperature spin dynamics by a dynamic mean-field theory — •Timo Gräßer¹, Kristine Rezai², Alexander O. Sushkov², and Götz S. Uhrig¹ — ¹Condensed Matter Theory, TU Dortmund University, Otto-Hahn Straße 4, 44221 Dortmund, Germany — ²Department of Physics, Boston University, Boston, MA 02215, USA

We develop a dynamic mean-field theory for spin systems at infinite temperature (spinDMFT) [1]. The idea is to replace the large environment of a spin by a dynamic mean-field which displays a random Gaussian temporal evolution. Its autocorrelations are self-consistently linked to the quantum mechanic expectation values of spin-spin correlations. This approach becomes exact in the limit of large lattice coordination numbers. We improve the approach by considering spin clusters quantum-mechanically (cluster spinDMFT). The extended model is able to describe dynamic spin correlations measured in recent experiments [2] where an inhomogeneous spin-12 ensemble on a diamond surface is probed using nitrogen-vacancy centers as sensors.
[1] T. Gräßer et al., Phys. Rev. Research 3, 043168 (2021).
[2] K. Rezai et al., arXiv:2207.10688 (2022).