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Semimetallic and se...
Semimetallic and semiconductor properties of some superhard and ultrahard fullerites in the range 300-2 K
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Buga, Sergei G. (författare)
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Blank, Vladimir D. (författare)
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Dubitsky, Gennadii A. (författare)
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- Edman, Ludvig (författare)
- Umeå universitet,Institutionen för fysik
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Zhu, Xiaomei (författare)
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Nyeanchi, Emmanuel B. (författare)
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- Sundqvist, Bertil (författare)
- Umeå universitet,Institutionen för fysik
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(creator_code:org_t)
- Elsevier B.V. 2000
- 2000
- Engelska.
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Ingår i: Proceedings of the 5th IUMRS International Conference on Advanced Materials, Beijing 1999. - : Elsevier B.V.. ; , s. 1009-1015
- Relaterad länk:
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https://urn.kb.se/re...
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https://doi.org/10.1...
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Abstract
Ämnesord
Stäng
- Electrical resistivity and magnetoresistance were measured on samples with disordered structures synthesized from pure C60 and C70 at pressures in the range 8–12.5 GPa and temperatures of 900–1500 K. Different types of behaviour were observed: semimetallic, VRH and semiconducting, depending on the degree of disorder and the particular short-range order of the samples. A negative magnetoresistance was observed at T<10 K on samples with a semimetallic type of conductivity synthesized at 8 GPa pressure. The temperature dependence of resistivity in the sample with a disordered crystalline structure based on 3D-polymerized C60 molecules fits Mott's law for hopping conductivity. T3/2, T2 and T4 dependencies of conductivity are observed for samples with densities of 2.8 and 3.05 g/cm3 synthesized at a pressure of 12.5 GPa. The effect of hydrostatic pressure on the resistivity of cross-linked layered carbon structures obtained from C60 at P=8 GPa, T=1600 K was investigated up to 0.6 GPa at room temperature. An approximately linear decrease of resistivity was observed with a very small value of the derivative d ln ρ/dp=0.06 /GPa, which correlates with a very low compressibility of the material.
Ämnesord
- NATURVETENSKAP -- Fysik -- Den kondenserade materiens fysik (hsv//swe)
- NATURAL SCIENCES -- Physical Sciences -- Condensed Matter Physics (hsv//eng)
Nyckelord
- Fullerenes
- C60
- high pressure synthesis
- polymer
- fullerene polymer
- semimetal
- semiconductor
- variable range hopping
- disorder
- resistance
- magnetoresistance
- pressure dependence
- Condensed matter physics
- Kondenserade materiens fysik
- fysik
- Physics
Publikations- och innehållstyp
- ref (ämneskategori)
- kon (ämneskategori)