Sablikov Vladimir A., Shchamkhalova Bagun S. Metastable and spin-polarized states in electron systems with localized electron–electron interaction. Physica E: Low-dimensional Systems and Nanostructures , 2014 , 59. С. 75-82. ISSN 13869477
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Текст
Physica E 59 (2014) 75–82[Metastable and spin-polarized states_]PHYSE11475.pdf Загрузить (977kB) | Предварительный просмотр |
Аннотация
We study the formation of spontaneous spin polarization in inhomogeneous electron systems with pair interaction localized in a small region that is not separated by a barrier from surrounding gas of non-interacting electrons. Such a system is interesting as a minimal model of a quantum point contact in which the electron–electron interaction is strong in a small constriction coupled to electron reservoirs without barriers. Based on the analysis of the grand potential within the self-consistent field approximation, we find that the formation of the polarized state strongly differs from the Bloch or Stoner transition in homogeneous interacting systems. The main difference is that a metastable state appears in the critical point in addition to the globally stable state, so that when the interaction parameter exceeds a critical value, two states coexist. One state has spin polarization and the other is unpolarized. Another feature is that the spin polarization increases continuously with the interaction parameter and has a square-root singularity in the critical point. We study the critical conditions and the grand potentials of the polarized and unpolarized states for one-dimensional and two-dimensional models in the case of extremely small size of the interaction region.
| Тип объекта: | Статья |
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| Авторы на русском. ОБЯЗАТЕЛЬНО ДЛЯ АНГЛОЯЗЫЧНЫХ ПУБЛИКАЦИЙ!: | В.А. Сабликов Б.С. Щамхалова |
| Подразделения (можно выбрать несколько, удерживая Ctrl): | 199 лаб. теоретических проблем микроэлектроники |
| URI: | http://cplire.ru:8080/id/eprint/2540 |
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