Metal-semiconductor-transition observed in Bi{sub 2}Ca(Sr, Ba){sub 2}Co{sub 2}O{sub 8+δ} single crystals

Journal Article · Mon Jul 28 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4891845· OSTI ID:22311197

Dong, Song-Tao ^[1]; Zhang, Bin-Bin; Zhang, Lun-Yong; Yao, Shu-Hua; Zhou, Jian; Zhang, Shan-Tao; Gu, Zheng-Bin; Chen, Yan-Feng ^[1]

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1. National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China)

Electrical property evolution of Bi{sub 2}AE{sub 2}Co{sub 2}O{sub 8+δ} single crystals (AE = Ca, Sr and Ba) is systematically explored. When AE changes from Ca to Ba, the electrical property of Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+δ} and Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+δ} demonstrates semiconductor-like properties. But Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+δ} shows the metallic behavior. Analysis of temperature-dependent resistance substantiates that from metallic Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+δ} to semiconductor-like Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+δ} can be attributed to Anderson localization. However the semiconductor behaviour of Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+δ} and Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+δ} is related to electronic correlations effect that is inferred by large negative magnetoresistance (∼70%). The theoretical electronic structures and valence X-ray photoemission spectroscopy substantiate that there is a relative large density of state around Fermi level in Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+δ} compared with other two compounds. It suggests that Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+δ} is more apt to be metal in this material system.

• OSTI ID: 22311197
• Journal Information: Applied Physics Letters, Vol. 105, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM COMPOUNDS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
COBALT COMPOUNDS
CORRELATIONS
ELECTRONIC STRUCTURE
EVOLUTION
FERMI LEVEL
MAGNETORESISTANCE
METALS
MONOCRYSTALS
OXYGEN COMPOUNDS
PHOTOEMISSION
SEMICONDUCTOR MATERIALS
SPECTROSCOPY
STRONTIUM COMPOUNDS
TEMPERATURE DEPENDENCE
X RADIATION