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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 detected two spontaneous precession frequencies in antiferromagnetic pure LaMnO3, the end member of different families of charge-doped manganites. The muon site and local field orientation are identified for one frequency, which provides a measure of the staggered magnetization. We present additional zero and longitudinal field muon relaxation data on an LaMnO3.045 sample in which a new regime appears above an intermediate temperatureT*, where regions of magnetic order coexist with domains of fluctuating moments. These results are discussed in terms of nucleation of the ordered phase in a superparamagnetic matrix.

The model developed to interpret holographic and out-of-focus images of superconducting vortices or fluxons in thin specimens has been implemented to treat effects such as misorientation or even distortion of the flux line. It is shown that in this way the anomalous shape of some globules in out-of-focus images of the flux line lattice as well as the local trend of the interference fringes in holographic reconstructed images can be satisfactorily interpreted.

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.