Temperature dependent conductivity and thermoelectric power of the iodine doped poly(vinyl alcohol)–Cu2+ chelate
| Autor: | Sejung Ahn, Chong-Su Cho, Yukyung Kim, Youngwoo Nam, Jihyun Park, Mi-Kyong Yoo, Yung Woo Park, Honam Yoo |
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| Rok vydání: | 2009 |
| Předmět: |
Magnetoresistance
Condensed matter physics Chemistry Mechanical Engineering Metals and Alloys Mineralogy Conductivity Atmospheric temperature range Condensed Matter Physics Thermal conduction Electronic Optical and Magnetic Materials Metal Mechanics of Materials Electrical resistivity and conductivity Seebeck coefficient visual_art Materials Chemistry visual_art.visual_art_medium Quantum tunnelling |
| Zdroj: | Synthetic Metals. 159:2086-2090 |
| ISSN: | 0379-6779 |
| Popis: | We have investigated the temperature dependence of electrical conductivity and thermoelectric power (TEP) at 1.7 K T 2+ chelate. We observed intrinsic metallic temperature dependence of resistivity from room temperature to 68 K with a broad minimum [ ρ (68 K)/ ρ (300 K) ∼0.75], which has not been observed previously in similar organo metallic complexes. There occurs an unusual metal-insulator transition at T ∼68 K and the resisitivity increases upon cooling below 68 K. However, the low temperature resistivity becomes finite (instead of going to infinity), [ρ(1.7 K)/ ρ (300 K) ∼0.98] indicating that a quantum mechanical tunneling conduction is dominant at this low temperature. It is remarkable that the resistivity at 1.7 K is as small as that of room temperature. Such unusual temperature dependence of conductivity could be understood as thermally assisted hopping conduction between metallic islands. However, the observed intrinsic metallic temperature dependence of resistivity implies that such hopping conduction barrier is not important at high temperature ( T > 68 K). The intrinsic metallic characteristics are confirmed by the quasi-linear temperature dependence of TEP for the whole measured temperature range (1.7 K T T |
| Databáze: | OpenAIRE |
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