Our work in the past few years has been focused on local NMR (nuclear magnetic resonance) and μSR (muon spin resonance) studies of pure Heisenberg isotropic triangular lattices with nearest neighbour couplings, a prerequisite for reaching the ideal spin liquid case. In the case of chromates, although S ≤ 3/2, the combination of the weakness of the Cr3+ single-ion anisotropy and that of an exchange interaction resulting from a direct overlap of the Cr3+ orbitals allows us to tackle these properties. We were recently able to single out, in the triangular compound NaCrO2, an original dynamical crossover regime in a broad range of T between the peak in specific heat and a low T static ground state. Moving to the corner-sharing geometry of Kagome bilayers (Ba2Sn2ZnGa 10-7pCr7pO22 and SrCr9pGa 12-9pO19), we illustrate all the potential of local studies (NMR and μSR) for revealing some key aspects of the physics of these compounds, namely fluctuations, susceptibility, the impact of dilution defects which generate an extended response of the spin lattice as well as their puzzling spin glass state. These results are compared to the case of volborthite which features S ≤ 1/2 spins on a corner-sharing, probably anisotropic, antiferromagnetic Kagome lattice.
All Science Journal Classification (ASJC) codes
- General Materials Science
- Condensed Matter Physics