Ferromagnetic spin fluctuations in the Kagome Metal Sc₃Mn₃Al₇Si₅ revealed by ²⁷Al NMR

Recently, there has been growing interest in metals with Kagome lattice structures, primarily due to possible topological nontrivial electronic states originating from flat band structures. Sc₃Mn₃Al₇Si₅ with a hexagonal structure (space group P6₃/mmc) has been reported to be a rare metallic system with Mn ions forming the Kagome lattice. Magnetic susceptibility, specific heat, and neutron diffraction measurements show no long-range magnetic order down to 1.8 K. To investigate the magnetic and electronic states of Sc₃Mn₃Al₇Si₅ from a microscopic point of view, we have carried out ²⁷Al nuclear magnetic resonance (NMR) measurements in the temperature region between 1.5 K and 300 K [1]. From our analysis using the NMR results of the temperature dependences of the NMR spectrum and the nuclear spin-lattice relaxation time T₁, ferromagnetic spin fluctuations were found to develop with decreasing temperatures. In the talk, I will also report the results of ⁵⁵Mn NMR in addition to the ²⁷Al NMR and discuss the peculiar metallic state of Sc₃Mn₃Al₇Si₅.

  

[1] Q.-P. Ding et al., Phys. Rev. B 112, L121105 (2025).