Static and dynamical magnetic and electronic properties of the kagome metal ${\mathrm{Sc}}_3{\mathrm{Mn}}_3{\mathrm{Al}}_7{\mathrm{Si}}_5$ have been investigated by ${}^{27}\mathrm{Al}$ nuclear magnetic resonance (NMR) measurements. Two distinct ${}^{27}\mathrm{Al}$-NMR signals with two different values of quadrupolar frequencies of ${\nu }_{\mathrm{Q}}$ = 1.55(2) and 1.07(2) MHz are observed, which are assigned to Al(1) and Al(2), respectively. From the detailed NMR spectrum measurements under three different magnetic field directions and the density functional theory calculations, the principal axes of the electric field gradient for each Al site have been determined. The temperature dependence of Knight shift ($K$) shows a similar temperature dependence of the DC magnetic susceptibility $\chi$ except for the low-temperature region below $\sim 50$ K where $K$ is almost constant while $\chi$ keeps increasing, which suggests that the increase in $\chi$ at low temperatures is not intrinsic. ${}^{27}\mathrm{Al}$ spin-lattice relaxation rate divided by temperature ($1/T_{1}T$) is found to be constant, confirming the metallic state of ${\mathrm{Sc}}_3{\mathrm{Mn}}_3{\mathrm{Al}}_7{\mathrm{Si}}_5$ from a microscopic point of view. Based on a Korringa ratio analysis using the $T_1$ and $K$ data, ferromagnetic fluctuations are found to dominate in ${\mathrm{Sc}}_3{\mathrm{Mn}}_3{\mathrm{Al}}_7{\mathrm{Si}}_5$. These fluctuations are suggested to be very slow with frequencies on the order of kilohertz or lower.

Close

PrevNext

View figure in article

• Fluctuations
• Magnetism
• Kagome metal
• Strongly correlated systems
• Nuclear magnetic resonance