Magnetic frustration and magnetic correlations in YbMn₂Sb₂ single crystals

The crystal growth and the structural, transport and magnetic characterization of the magnetically frustrated YbMn₂Sb₂ single crystals are reported. The crystals show a trigonal symmetry, where corrugated honeycomb layers of MnSb are separated by Yb atoms. No structural transition was observed down to 22 K. The resistivity measurements show a predominantly insulating behavior. The combined resistivity, dc and ac susceptibility, and heat capacity measurements confirm successive transitions at 230 K, 116 K and 40 K, being the transition at T_N =116 K due to the Mn⁺² lattice antiferromagnetic ordering. Muon spin rotation experiments (µSR) reveal a more complicated scenario, with a complex temperature dependence of the magnetic volume fraction and a several order of magnitude variation of the relaxation rate, with its maximum at approximately 40 K.