SKM 2023 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 45: Correlated Electrons: 1D Theory

TT 45.2: Vortrag

Donnerstag, 30. März 2023, 09:45–10:00, HSZ 103

Electron spin resonance as a direct probe of spinon interactions in a S=1/2 chain — •Kirill Povarov^1,2, Timofei Soldatov³, Ren-Bo Wang⁴, Andrey Zheludev¹, Alexander Smirnov³, and Oleg Starykh⁴ — ¹Laboratory for Solid State Physics, ETH Zürich — ²Dresden High Magnetic Field Laboratory (HLD), Helmholtz-Zentrum Dresden-Rossendorf (HZDR) — ³P.L. Kaptiza Institute for Physical Problems RAS — ⁴Department of Physics and Astronomy, University of Utah

The presence of well-hidden backscattering between the fractionalized spinon excitations was known to be a somewhat exotic part of the S=1/2 chain physics. However, its dramatic consequences for the dynamics were realized recently [1]. They are challenging for observation, as applied field and nonzero momenta are simultaneously required. We have succeeded in the experimental verification of these effects using electron spin resonance as probe [2]. Our observations are enabled by the specific pattern of Dzyaloshinskii–Moriya interactions in our target material K₂CuSO₄Br₂. Description of the observed spectrum requires accounting for the backscattering on a qualitative level. Quantitative analysis allows us to estimate the backscattering constant as 2.4J (intrachain exchange), in agreement with the renormalization group predictions. This work has been supported by SNSF Division II (ETHZ), the NSF CMMT grant DMR-1928919 (U. Utah), and the RSF Grant 17-12-01505 (IPP).
[1] A. Keselman et al., PRL 125, 187201 (2020)
[2] K. Povarov et al., PRL 128, 187202 (2022) Editor’s Suggestion