A triad of high-field magnetic transitions in V ₅ S ₈

We report the observation of an unexpected phase transition at high magnetic fields between the spin-flop and spin-flip transitions in the d-electron antiferromagnetic metal V 5 S 8 . High-precision magnetic, thermal and electrical transport measurements enable the transitions to be tracked up to fields as high as 35 T and at temperatures down to the milli-Kelvin range revealing three distinct magnetic quantum phase transitions. We present a model that finds agreement with our observation of a triad of spin transitions involving two sublattices with frustrated inter-and intra-sublattice spin couplings.