Critical magnetic fields of superconducting aluminum-substituted Ba{sub 8}Si{sub 42}Al{sub 4} clathrate

Journal Article · Sun Jun 07 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4921702· OSTI ID:22412867

Li, Yang; Garcia, Jose; Lu, Kejie; Shafiq, Basir ^[1]; Franco, Giovanni; Lu, Junqiang ^[2]; Rong, Bo ^[3]; Chen, Ning; Liu, Yang ^[4]; Liu, Lihua; Song, Bensheng; Wei, Yuping ^[5]; Johnson, Shardai S.; Luo, Zhiping ^[6]; Feng, Zhaosheng ^[7]

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1. School of Engineering, University of Puerto Rico at Mayaguez, Mayaguez, Puerto Rico 00681-9000 (United States)
2. Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681 (United States)
3. Communications Research Centre (CRC), Industry Canada, 3701 Carling Avenue, Box 11490, Station H, Ottawa, Ontario K2H 8S2 (Canada)
4. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)
5. Department of Physics, University of Science and Technology Beijing, Beijing 100083 (China)
6. Department of Chemistry and Physics, Fayetteville State University, Fayetteville, North Carolina 28301 (United States)
7. Department of Mathematics, University of Texas-Pan American, Edinburg, Texas 78541 (United States)

In recent years, efforts have been made to explore the superconductivity of clathrates containing crystalline frameworks of group-IV elements. The superconducting silicon clathrate is unusual in that the structure is dominated by strong sp{sup 3} covalent bonds between silicon atoms, rather than the metallic bonding that is more typical of traditional superconductors. This paper reports on critical magnetic fields of superconducting Al-substituted silicon clathrates, which were investigated by transport, ac susceptibility, and dc magnetization measurements in magnetic fields up to 90 kOe. For the sample Ba{sub 8}Si{sub 42}Al{sub 4}, the critical magnetic fields were measured to be H{sub C1} = 40.2 Oe and H{sub C2} = 66.4 kOe. The London penetration depth of 4360 Å and the coherence length 70 Å were obtained, whereas the estimated Ginzburg–Landau parameter of κ = 62 revealed that Ba{sub 8}Si{sub 42}Al{sub 4} is a strong type-II superconductor.

• OSTI ID: 22412867
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 21; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM SILICIDES
BARIUM COMPOUNDS
CHEMICAL BONDS
COHERENCE LENGTH
CRITICAL FIELD
MAGNETIC SUSCEPTIBILITY
MAGNETIZATION
PENETRATION DEPTH
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TYPE-II SUPERCONDUCTORS