Role of oxygen content in electronic structures of Ba0.6K0.4BiO3–δ

✍ Scribed by Ming Li

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 217 KB
• Volume: 64
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1997)64:6<703::aid-qua7>3.0.co;2-#

✦ Synopsis

The band structure calculations on the K-doped superconductor Ba K BiO were carried out, and the effect of the oxygen content on its electronic 0.6 0.4 3᎐␦ structures was studied in the present work. The results show that the variation in the oxygen content caused by the partial substitution of K for Ba has a great effect on its electronic structure. The oxygen vacancies cause the saddle point singularity to be displaced gradually as the oxygen content is decreased, whereas the band structure is only translated a little and remains unchanged in shape, which reflects the non-rigidbandlike behavior of Ba K BiO in the presence of the oxygen vacancies. When the 0.6 0.4 3᎐␦ saddle point singularity is displaced and lies at the Fermi level E , the total density of f Ž . states at E , N E , has the highest value which is twice as large as that of the f f Ba K BiO compound without the oxygen vacancies. These results reveal the important 0.6 0.4 3 role of the oxygen content in the Ba᎐K᎐Bi᎐O superconducting system.