Inhomogeneities in Manganites: The Case of La1− x Ca x MnO3
| Autor: | J. J. Neumeier, G. Papavassiliou, J. A. Fernandez-Baca, A. L. Cornelius |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Superconductivity
Physics Condensed matter physics Scanning tunneling spectroscopy Context (language use) Polaron law.invention Condensed Matter::Materials Science Ferromagnetism law Condensed Matter::Strongly Correlated Electrons Scanning tunneling microscope Nuclear quadrupole resonance Phase diagram |
| Zdroj: | Springer Series in Solid-State Sciences ISBN: 9783642077531 |
| DOI: | 10.1007/978-3-662-05244-0_11 |
| Popis: | The theoretical analysis presented in previous chapters has clearly unveiled a previously unknown feature of simple models for manganites: there is an intrinsic tendency to electronic phase separation. Once the long-range Coulombic interaction is considered, as well as the effect of pinning centers and disorder, the macroscopic phase separation becomes a microscopic inhomogeneous state. Similar ideas have been analyzed before in the context of high-temperature superconductors (see [1.3] and Chap. 1), and it is rapidly becoming a unifying theme in the study of transition-metal oxides, and even in some non-oxide compounds. In this chapter, we describe experimental results for manganites focusing on the issue of inhomogeneities in La1- x Ca x MnO3 (LCMO). The reader will find that the evidence for inhomogeneities in LCMO is simply overwhelming. Figure 11.1, reproduced from Moreo et al. [1.10], shows the phase diagram of LCMO containing words reproduced from the experimental literature, at the temperature and hole density of those experiments. Clearly, in all the phases, including the ferromagnetic metallic one, and even at high temperatures, inhomogeneities have been unveiled. Experimentalists use a variety of names to describe their results, such as “droplets”, “domains”, “clusters”, “polarons”, and others, but they all refer to the same notion: the system is inhomogeneous at small length scales. |
| Databáze: | OpenAIRE |
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