Search

We present a study performed on several LaMnO3+x/2 compositions. Detailed analysis around x=0.09 detects phase separation between a higher transition, Tc, and a lower one TN, with coexisting fluctuating and magnetically ordered clusters (the Neel point, TN, being the onset of an inhomogeneous non-collinear antiferromagnetic order detected by neutrons). The ordered clusters give rise to an extremely fast, static Kubo–Toyabe muon depolarization, while mixed static and dynamic local fields are detected inside the fluctuating clusters. Below TN precession frequency lines are resolved, despite the huge broadening introduced by localized Mn4+ ordered moments. A phase diagram is obtained and briefly discussed in the context of electronic phase separation.

We present a closed expression for the muon longitudinal field relaxation function which interpolates between the concentrated and the dilute spin glass function, originally introduced by Uemura et al. (Phys. Rev. B 31 (1985) 546.) A fast computational algorithm for a data-fitting routine is outlined and an application to an unconventional disordered magnetic system is pointed out.