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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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SUPPRESSION OF SUPERCONDUCTIVITY AND THE OVERDOPED REGION IN HGBA2CUO4+DELTAстатья
Информация о цитировании статьи получена из
Scopus,
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 9 ноября 2013 г.
- Авторы: LOUREIRO SM, ALEXANDRE ET, ANTIPOV EV, CAPPONI JJ, DEBRION S., SOULETIE B., THOLENCE JL, MAREZIO M., HUANG Q., SANTORO A.
- Журнал: Physica C: Superconductivity and its Applications
- Том: 243
- Номер: 1-2
- Год издания: 1995
- Издательство: Elsevier BV
- Местоположение издательства: Netherlands
- Первая страница: 1
- Последняя страница: 9
- DOI: 10.1016/0921-4534(94)02419-7
- Аннотация: For the first time an overdoped, non-superconducting Hg-1201 phase was obtained by a high-pressure technique. The formal copper valence determined by iodometric titration was found to be +2.28(3). Superconducting Hg-1201 with T-c=35 K and upsilon(Cu)=+2.20(3) was obtained by using the same technique and the same precursor, but which had been previously heat-treated. Further heat treatment of the sample increased T-c up to 91 K and reduced upsilon(Cu) to +2.13(3). We show that in the overdoped region of the Hg-1201 system the Cu valence can be changed by varying the precursor heat treatment. The instability of the overdoped phases makes it difficult to achieve the same results by heat-treating the as-prepared samples. A neutron powder diffraction study carried out on the overdoped non-superconducting sample resulted in a value of delta=0.23(3). The formal copper valence obtained by iodometric titration and in the structural study can be reconciled if the presence of CO32- defects on the Hg layers is assumed, or if a formal valence of -1 is adopted for the doping oxygen atoms.
- Добавил в систему: Антипов Евгений Викторович