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Updated: Aug 13, 2026
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Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Magnetic filaments in resistive manganites
1Service de Physique de l'Etat Condensé, DSM/DRECAM-CNRS URA 2464, CEA-Saclay, 91191 Gif-sur-Yvette cedex, France. mviret@cea.fr
Physical Review Letters
|December 17, 2004
Summary
Magnetic phase separation in Pr0.67Ca0.33MnO3 manganites forms ferromagnetic filaments. Localized charge carriers mediate this via hopping exchange, creating a unique magnetic and transport state.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Manganites exhibit complex magnetic phase separation.
- Understanding the interplay of charge, spin, and lattice is crucial.
Purpose of the Study:
- Investigate the magnetic phase separation in Pr0.67Ca0.33MnO3 single crystals.
- Elucidate the mechanism behind the filamentary magnetic structures.
Main Methods:
- Polarized small-angle neutron scattering (SANS) was employed.
- Monte Carlo simulations were used to validate theoretical models.
Main Results:
- SANS spectra revealed a fractal dimension consistent with nanometric ferromagnetic filaments.
- Evidence for coexistence of hopping exchange and superexchange was found.
Conclusions:
- Localized charge carrier hopping contributes to the filamentary phase separation.
- A self-consistent model of magnetism and transport explains the observed phenomena.
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