著者

Murakami Katsuhisa Kadowaki Takuya Fujita Jun-ichi

出版者

American Institute of Physics

雑誌

Applied physics letters (ISSN:00036951)

巻号頁・発行日

vol.102, no.4, pp.043111, 2013-01

被引用文献数

28 2

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From the analysis of the ratio of D peak intensity to G peak intensity in Raman spectroscopy, electron beam irradiation with energies of 100 eV was found to induce damage in single-layer graphene. The damage becomes larger with decreasing electron beam energy. Internal strain in graphene induced by damage under irradiation is further evaluated based on G peak shifts. The dose-dependent internal strain was approximately 2.22% cm2/mC at 100 eV and 2.65 × 10−2% cm2/mC at 500 eV. The strain induced by the irradiation showed strong dependence on electron energy.

著者

Fujita Jun-ichi Tachi Masashi Murakami Katsuhisa Sakurai Hidehiro Morita Yuki Higashibayashi Shuhei Takeguchi Masaki

出版者

American Institute of Physics

雑誌

Applied physics letters (ISSN:00036951)

巻号頁・発行日

vol.104, no.4, pp.043107, 2014-01

被引用文献数

4

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We found that electron-beam irradiation of sumanene aggregates strongly enhanced their transformation into a graphitic carbon cage, having a diameter of about 20 nm. The threshold electron dose was about 32 mC/cm2 at 200 keV, but the transformation is still induced at 20 keV. The transformation sequence suggested that the cage was constructed accompanied by the dynamical movement of the transiently linked sumanene molecules in order to pile up inside the shell. Thus, bond excitation in the sumanene molecules rather than a knock-on of carbon atoms seems to be the main cause of the cage transformation.

著者

Fujita Jun-ichi Takahashi Teppei Ueki Ryuichi Hikata Takeshi Okubo Soichiro Utsunomiya Risa Matsuba Teruaki

出版者

American Vacuum Society

雑誌

Journal of vacuum science & technology B (ISSN:10711023)

巻号頁・発行日

vol.30, no.3, pp.03D105, 2012

被引用文献数

4

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The authors demonstrated a new method for inducing enormous shrinkage in single-walled carbon nanotube bundles by applying low energy electron beam irradiation along with supersonic vibration, and a maximum shrinkage rate of −100% cm2/C was obtained under electron acceleration of 1 keV. The characteristic feature of the shrunken single-walled carbon nanotubes was a wavy deformation that affected the entire bundle. The authors believe that a uniaxial stress induced by the supersonic vibration broke the equilibrium of the internal stress and allowed the uniform accumulation of defects under low energy electron beam excitation. The wavy deformation of the single-walled carbon nanotubes resulted in the enormous shrinkage of the bundle.