On the role of lattice defects at O(1) in YBa2Cu3O7−δ

✍ Scribed by Hiroshi Tatewaki

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 92 KB
• Volume: 265
• Category: Article
• ISSN: 0375-9601
• DOI: 10.1016/s0375-9601(99)00882-8

✦ Synopsis

The electronic structure of the YBa Cu O family is discussed, using cluster models embedded in the large ionic cage. 2 3 7 Ž . Ž . Ž . The 2p holes at O 1 , two different types of 3d holes, 3d at Cu 2 and 3d at Cu 1 , all have resulted from the p x 2yy 2 z 2yx 2 calculations and are consistent with experiment. To generate p holes on the CuO plane, introduction of the lattice defects at 2 Ž . Ž . O 1 s is shown to be necessary. Furthermore, the O 1 defects bring the ground state with two adjacent p holes, p exciton-like low excited state, and stable electron affinity states, showing the charge fluctuations in this region. Energetics are also treated.