Magnetism and orbitally driven spin-singlet states in Ru oxides: a muon-spin rotation study

Abstract

We have used zero-field muon-spin rotation to study the local magnetic properties of SrRuO₃, Y₂Ru₂O₇, and La₂RuO₅. While SrRuO₃ and Y₂Ru₂O₇ give rise to coherent precession signals, in La₂RuO₅ we find no signature of long range magnetic order below the structural transition, but observe relaxation consistent with that expected due to a dimerization into spin-singlet states. In Y₂Ru₂O₇ we observe two precession signals with different temperature dependences, consistent with the nature of the noncollinear ordering being temperature dependent.