Item type |
デフォルトアイテムタイプ(フル)(1) |
公開日 |
2020-12-15 |
タイトル |
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タイトル |
Simultaneous structure and carrier tuning of dimorphic clathrate Ba_8Ga_<16>Sn_<30> |
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言語 |
en |
作成者 |
Suekuni, K.
Avila, M. A.
Umeo, K.
Fukuoka, H.
Yamanaka, S.
Nakagawa, T.
Takabatake, T.
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アクセス権 |
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アクセス権 |
open access |
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アクセス権URI |
http://purl.org/coar/access_right/c_abf2 |
権利情報 |
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言語 |
ja |
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権利情報 |
©2008 American Physical Society |
内容記述 |
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内容記述タイプ |
Other |
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内容記述 |
We report structural, transport, and thermal properties of carrier-tuned Ba_8Ga_<16>Sn_<30> single crystals with the type-1 clathrate structure (β phase), demonstrating that Ba_8Ga_<16>Sn_<30> is a unique thermoelectric clathrate material wherein both the structure type and the carrier type are tunable. The results are compared with the properties of the better known type-8 structure (α phase) and of A_8Ga_<16>Ge_<30> (A=Sr,Eu). Differential thermal analysis and powder x-ray diffraction show that both phases are stable up to their virtually identical melting point of 520±3 °C. Refinements of single-crystal x-ray diffraction data indicate that the Ba(2) guest ion in the tetrakaidecahedron occupies the off-center 24k sites which are 0.43–0.44 Å away from the centered 6d site. The temperature-linear coefficient of the specific heat is 29 mJ/mol K^2 for both n- and p-type carriers in the β phase, four times larger than that for the α phase, suggesting contributions from tunneling of the Ba(2) guest ions between off-center minima. Analysis of specific heat with a soft-potential model (SPM) gives a characteristic energy of 20 K for the Ba(2) vibration, significantly lower than 50 K for the α phase and in fact the lowest among type-1 clathrates. The lattice thermal conductivities κL for the β phase with both charge carrier types are very similar and show a glasslike temperature dependence. This behavior in κL(T) is also described using SPM analysis, where it is found that the coupling strength between guest modes and acoustic phonons for the β phase is significantly larger than that for Sr_8Ga_<16>Ge_<30>. |
内容記述 |
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内容記述タイプ |
Other |
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内容記述 |
論文 |
出版者 |
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言語 |
en |
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出版者 |
American Physical Society |
言語 |
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言語 |
eng |
資源タイプ |
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資源タイプ |
journal article |
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資源タイプ識別子 |
http://purl.org/coar/resource_type/c_6501 |
出版タイプ |
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出版タイプ |
VoR |
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出版タイプResource |
http://purl.org/coar/version/c_970fb48d4fbd8a85 |
識別子 |
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識別子 |
http://hdl.handle.net/20.500.12000/47496 |
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識別子タイプ |
HDL |
関連情報 |
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識別子タイプ |
DOI |
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関連識別子 |
https://doi.org/10.1103/PhysRevB.77.235119 |
関連情報 |
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識別子タイプ |
DOI |
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関連識別子 |
https://doi.org/10.1103/PhysRevB.77.235119 |
収録物識別子 |
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収録物識別子タイプ |
ISSN |
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収録物識別子 |
2469-9950 |
収録物識別子 |
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収録物識別子タイプ |
ISSN |
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収録物識別子 |
2469-9969 |
収録物名 |
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言語 |
en |
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収録物名 |
Physical Review B |
書誌情報 |
巻 77,
号 23,
発行日 2008-06-25
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