| Project/Area Number |
13304026
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
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| Research Institution | Tokyo Metropolitan University |
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Principal Investigator |
KATAURA Hiromichi Tokyo Metropolitan University, Graduate School of Science, Research Associate, 理学研究科, 助手 (30194757)
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| Co-Investigator(Kenkyū-buntansha) |
TSUKAGOSHI Kazuhito Riken, Low temperature Physics Laboratory, Research, 低温工学研究室, 研究員 (50322665)
KODAMA Takashi Tokyo Metropolitan University, Graduate School of Science, Research Associate, 理学研究科, 助手 (20285092)
SUZUKI Shinzo Tokyo Metropolitan University, Graduate School of Science, Research Associate, 理学研究科, 助手 (10226516)
FUJIWARA Akihiko Japan Advanced Institute of Science and Technology, School of Materials Science, Associate Professor, 大学院・材料科学研究科, 助教授 (70272458)
YOSHIOKA Hideo Nara Woman University, Faculty of Science, Associate Professor, 理学部, 助教授 (40252225)
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| Project Period (FY) |
2001 – 2003
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| Keywords | carbon nanotube / Tomonaga-Luttinger liquid / Raman scattering / Optical property / Photoemission spectroscopy / peapod / metal encapsulation / single wall nanotube |
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| Research Abstract |
We have synthesized high-quality single-wall carbon nanotubes by the laser ablation methods and revealed interesting natures of them as listed below.
1.We have first confirmed one-dimensional van Hove singularities by means of photoemission spectroscopy by using highly purified single-wall carbon nanotubes. Furthermore, we have fond two power law dependences of electronic density of states (DOS). The first one is power law dependence of DOS on the binding energy and the second one is power law of DOS at the Fermi level on the temperature. The exponents are 0.46 and 0.48, respectively that just agree with the theoretical predictions for the one-dimensional metallic system so called Tomonaga Luttinger liquid (TLL) system. Our result is the most reliable evidence that the TLL system is realized even in the bundle of single-wall carbon nanotubes.
2.The isolated nanotubes embedded in the support materials were synthesized by chemical vapor deposition of ethanol and the optical properties of them were measured. The sample shows very narrow radial breathing Raman peaks with the half width less than 1.5 cm-1. The Raman spectrum does not contain any peaks peculiar to the bundles. This new sample gave us useful information about electronic structure of carbon nanotubes and the selection rule of the optical transition.
3.When we introduced water molecules into carbon nanotubes, we found that water molecules transformed to ice-nanotubes at low temperature. By changing the diameter of carbon nanotubes we can control the diameter of ice-nanotube. We found that ice nanotube with different diameter has different freezing point. The larger diameter of ice-nanotube leads to the lower freezing point, which is opposite to the empirical rule.
4.We have synthesized single-wall carbon nanotubes encapsulating metallo-fullerenes and have done some spectroscopic measurements. Double wall carbon nanotube formation was also investigated by X-ray diffraction and Raman spectroscopy.
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