2007/07/11 by K. Mukherjee, A. Banerjee · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Rare-earth and actinide compounds #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.77.024430
published as Phys. Rev. B 77, 024430 (2008).
arxiv created 2007/07/11 · openalex publication_date 2008/01/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
An attempt is made to resolve the controversy related to the low temperature phase (ground state) of the low-doped ferromagnetic (FM)-insulator manganite through bulk magnetic measurements on La0.9Sr0.1MnO3 sample. It is shown that the FM phase, formed out of well defined transition in the low-doped system, becomes inhomogeneous with decrease in temperature. This inhomogeniety is considered to be an outcome of the formation of orbital domain state of eg electrons having hole rich (metallic) walls separating the hole deficient (insulating) regions. The resulting complexity brings in metastability and glassy behavior within the FM phase at low temperature, however, with no resemblance to spin glass, cluster glass, or reentrant phases. It shows aging effect without memory but magnetic relaxation shows signatures of intercluster interaction. The energy landscape picture of this glassy phase is described in terms of hierarchical model. Further, it is shown that this inhomogeneity disappears in La0.9Sr0.1MnO3.08 where the orbital domain state is destroyed by self-doping, resulting in reduction of Mn3+ and hence eg electrons. The ferromagnetic phase of the nonstoichiometric sample does not show glassy behavior. It neither follows ``hierarchical model'' nor ``droplet model'' generally used to explain glassy or inhomogeneous systems. Its magnetic response can be explained simply from the domain wall dynamics of otherwise homogeneous ferromagnet.