title: Cathodoluminescence microscopy and spectroscopy of micro- and nanodiamonds: an implication for laboratory astrophysics.
abstract: Color centers in selected micro- and nanodiamond samples were investigated by cathodoluminescence (CL) microscopy and spectroscopy at 298 K [room temperature (RT)] and 77 K [liquid-nitrogen temperature (LNT)] to assess the value of the technique for astrophysics. Nanodiamonds from meteorites were compared with synthetic diamonds made with different processes involving distinct synthesis mechanisms (chemical vapor deposition, static high pressure high temperature, detonation). A CL emission peak centered at around 540 nm at 77 K was observed in almost all of the selected diamond samples and is assigned to the dislocation defect with nitrogen atoms. Additional peaks were identified at 387 and 452 nm, which are related to the vacancy defect. In general, peak intensity at LNT at the samples was increased in comparison to RT. The results indicate a clear temperature-dependence of the spectroscopic properties of diamond. This suggests the method is a useful tool in laboratory astrophysics.
authors.affiliation: Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University, Kitashirakawaoiwake-cho, Sakyu-ku, Kyoto-shi 606-8502, Japan. gucsik@mailmax.hu
authors.forename: Arnold
authors.initials: A
authors.lastname: Gucsik
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Nishido
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Ninagawa
authors.forename: Ulrich
authors.initials: U
authors.lastname: Ott
authors.forename: Akira
authors.initials: A
authors.lastname: Tsuchiyama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kayama
authors.forename: Irakli
authors.initials: I
authors.lastname: Simonia
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Boudou