Optical study of 4f excitations in rare earth cuprates
Several recent examples are used to demonstrate that Raman and infrared spectroscopy can be successfully used as a novel experimental tool to study microscopic processes involving 4f electrons in rare earth (RE) cuprates. Raman-active crystal field (CF) excitations in Nd₂CuO₄ were measured under hyd...
Збережено в:
| Дата: | 2002 |
|---|---|
| Автор: | |
| Формат: | Стаття |
| Мова: | English |
| Опубліковано: |
Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
2002
|
| Назва видання: | Физика низких температур |
| Теми: | |
| Онлайн доступ: | http://dspace.nbuv.gov.ua/handle/123456789/130230 |
| Теги: |
Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Цитувати: | Optical study of 4f excitations in rare earth cuprates / V.Nekvasil // Физика низких температур. — 2002. — Т. 28, № 7. — С. 739-744. — Бібліогр.: 28 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-130230 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-1302302018-02-10T03:04:26Z Optical study of 4f excitations in rare earth cuprates Nekvasil, V. Магнетизм Several recent examples are used to demonstrate that Raman and infrared spectroscopy can be successfully used as a novel experimental tool to study microscopic processes involving 4f electrons in rare earth (RE) cuprates. Raman-active crystal field (CF) excitations in Nd₂CuO₄ were measured under hydrostatic pressure up to ∼7 GPa. The observed pressure-induced shifts of the CF levels were interpreted using density-functional-theory-based ab initio calculations and the superposition model. An infrared transmission study of the ⁴Ij, J=9/2, 11/2, 13/2 multiplets of Nd³⁺ in Nd₂CuO₄ reveals a splitting of the Kramers doublets of the order of a few cm⁻¹ due to the Nd-Cu exchange interaction. This study shows that these splittings can be described by an effective anisotropic exchange Hamiltonian for the Nd³⁺ ion expressed in terms of spherical tensor operators up to the sixth order. The isotropic term in the exchange Hamiltonian vanishes for symmetry reasons in this case. An analysis of the infrared transmission spectra in RE₁₊xBa₂₋xCu3O₆₊δ (RE=Nd,Sm) up to ∼ 10 000 cm⁻¹ indicates that, besides the regular sites, the RE ions also occupy Ba sites, even in the samples with the cation stoichiometry 1–2–3. 2002 Article Optical study of 4f excitations in rare earth cuprates / V.Nekvasil // Физика низких температур. — 2002. — Т. 28, № 7. — С. 739-744. — Бібліогр.: 28 назв. — англ. 0132-6414 PACS: 78.30.-j, 71.70.-d http://dspace.nbuv.gov.ua/handle/123456789/130230 en Физика низких температур Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| topic |
Магнетизм Магнетизм |
| spellingShingle |
Магнетизм Магнетизм Nekvasil, V. Optical study of 4f excitations in rare earth cuprates Физика низких температур |
| description |
Several recent examples are used to demonstrate that Raman and infrared spectroscopy can be successfully used as a novel experimental tool to study microscopic processes involving 4f electrons in rare earth (RE) cuprates. Raman-active crystal field (CF) excitations in Nd₂CuO₄ were measured under hydrostatic pressure up to ∼7 GPa. The observed pressure-induced shifts of the CF levels were interpreted using density-functional-theory-based ab initio calculations and the superposition model. An infrared transmission study of the ⁴Ij, J=9/2, 11/2, 13/2 multiplets of Nd³⁺ in Nd₂CuO₄ reveals a splitting of the Kramers doublets of the order of a few cm⁻¹ due to the Nd-Cu exchange interaction. This study shows that these splittings can be described by an effective anisotropic exchange Hamiltonian for the Nd³⁺ ion expressed in terms of spherical tensor operators up to the sixth order. The isotropic term in the exchange Hamiltonian vanishes for symmetry reasons in this case. An analysis of the infrared transmission spectra in RE₁₊xBa₂₋xCu3O₆₊δ (RE=Nd,Sm) up to ∼ 10 000 cm⁻¹ indicates that, besides the regular sites, the RE ions also occupy Ba sites, even in the samples with the cation stoichiometry 1–2–3. |
| format |
Article |
| author |
Nekvasil, V. |
| author_facet |
Nekvasil, V. |
| author_sort |
Nekvasil, V. |
| title |
Optical study of 4f excitations in rare earth cuprates |
| title_short |
Optical study of 4f excitations in rare earth cuprates |
| title_full |
Optical study of 4f excitations in rare earth cuprates |
| title_fullStr |
Optical study of 4f excitations in rare earth cuprates |
| title_full_unstemmed |
Optical study of 4f excitations in rare earth cuprates |
| title_sort |
optical study of 4f excitations in rare earth cuprates |
| publisher |
Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України |
| publishDate |
2002 |
| topic_facet |
Магнетизм |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/130230 |
| citation_txt |
Optical study of 4f excitations in rare earth cuprates / V.Nekvasil // Физика низких температур. — 2002. — Т. 28, № 7. — С. 739-744. — Бібліогр.: 28 назв. — англ. |
| series |
Физика низких температур |
| work_keys_str_mv |
AT nekvasilv opticalstudyof4fexcitationsinrareearthcuprates |
| first_indexed |
2023-10-18T20:59:33Z |
| last_indexed |
2023-10-18T20:59:33Z |
| _version_ |
1796151640714117120 |