Phase diagram of manganese oxidesстатья из журнала
Аннотация: We study theoretically the phase diagram of perovskite manganites taking into account the double degeneracy of the ${e}_{g}$ orbitals in a ${\mathrm{Mn}}^{3+}$ ion. A rich phase diagram is obtained in the mean-field theory at zero temperature as functions of $x$ (hole concentration) and ${J}_{S}$ (antiferromagnetic interaction between ${t}_{2g}$ spins). The global features of the phase diagram are understood in terms of the superexchange and double-exchange interactions, which strongly depend on the types of occupied ${e}_{g}$ orbitals. The strong electron correlation induces the orbital polarization, which controls the dimension of the conduction band. A sequential change of the spin and orbital structures with doping holes is consistent with the recent experiments. In particular, a metallic $A$-type (layered) antiferromagnetic state is found for $x\ensuremath{\sim}0.5$ with the uniform ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ orbital ordering. In this phase, calculated results suggest two-dimensional conduction and absence of the spin canting, which are observed experimentally. The effects of the Jahn-Teller distortion are also studied.
Год издания: 1998
Авторы: Ryo Maezono, Sumio Ishihara, Naoto Nagaosa
Издательство: American Physical Society
Источник: Physical review. B, Condensed matter
Ключевые слова: Magnetic and transport properties of perovskites and related materials, Advanced Condensed Matter Physics, Multiferroics and related materials
Другие ссылки: Physical review. B, Condensed matter (HTML)
arXiv (Cornell University) (PDF)
arXiv (Cornell University) (HTML)
arXiv (Cornell University) (PDF)
arXiv (Cornell University) (HTML)
arXiv (Cornell University) (PDF)
arXiv (Cornell University) (HTML)
arXiv (Cornell University) (PDF)
arXiv (Cornell University) (HTML)
Открытый доступ: green
Том: 58
Выпуск: 17
Страницы: 11583–11596