OBSERVATION OF INTERCALATION OF EXCESS OXYGEN IN BI2SR2CACU2O8-CRYSTAL(Y SINGLE)

Citation
Gs. Shekhawat et al., OBSERVATION OF INTERCALATION OF EXCESS OXYGEN IN BI2SR2CACU2O8-CRYSTAL(Y SINGLE), Applied physics letters, 67(22), 1995, pp. 3343-3345
Citations number
22
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
00036951
Volume
67
Issue
22
Year of publication
1995
Pages
3343 - 3345
Database
ISI
SICI code
0003-6951(1995)67:22<3343:OOIOEO>2.0.ZU;2-Y
Abstract
Effects arising from the intercalation of excess oxygen in Bi-O layer has been observed at room temperature using atomic force microscopy. T he excess oxygen is incorporated by oxygenating the pure sample. The o xygen is trapped between the alternating Bi-O layers along the b direc tion. This leads to a change in the local interatomic bond length alon g the b axis, while the periodicity remained invariant along the a axi s. In addition, in-plane atomically resolved structure of single cryst al has been imaged at room temperature using AFM. The lattice spacings indicate that the observed structure corresponds to the in-plane bism uth and oxygen positions. Furthermore, high-resolution scanning tunnel ing spectroscopy measurements show that oxygen doping increases the Bi -O layer density of states near the Fermi level giving rise to metalli city, whereas the pure sample reveals a semiconducting energy gap in t he tunneling spectrum. (C) 1995 American Institute of Physics.