Investigation of the Paramagnetic State of the Kagome Kondo Lattice YbV₆Sn₆: a ⁵¹V Nuclear Magnetic Resonance Study

The rare-earth intermetallic compounds RT₆Sn₆ (R = rare earth, T = V, Cr, Mn, Fe, Co) attract lots of recent scientific interest due to a novel interplay of Kondo screening, geometrical frustration, and kagome lattice network. The Ytterbium-based Kondo triangular-lattice YbV₆Sn₆ is a new member in this group discovered recently, which shows an antiferromagnetic transition at T_N ~ 0.4 K and has a rare realization of a triangular lattice network of Yb ions[1]. In this work, we present ⁵¹V nuclear magnetic resonance (NMR) study in YbV₆Sn₆ to investigate the local magnetic interactions and fluctuations in its paramagnetic state. Single-crystalline measurements under rotating magnetic field allowed us to determine the local spin susceptibility for different crystallographic axis directions. The spin-lattice (T₁) relaxation measurement found a development of strong anisotropy in the spin fluctuations below 20 K, with the in-plane fluctuations keep developing upon further cooling as well as reducing the field size. Notable in-plane angular dependence was also observed in T₁ at 5 K, the implication of which in relation to the possible local Yb spin fluctuations would be discussed.

 

[1] K. Guo et al, Phys. Rev. B 107, 205151 (2023)

[2] S. Park et al, under revision at Phys. Rev. B; arXiv: 2506.04563