- 著者
- Arai Hideyuki Kudo Hiroshi Tomita Shigeo Ishii Satoshi
- 出版者
- The Physical Society of Japan
- 雑誌
- Journal of the Physical Society of Japan (ISSN:00319015)
- 巻号頁・発行日
- vol.78, no.10, pp.104301, 2009-10
- 被引用文献数
- 5
We have specified the mechanism of suppressed electron emission from surfaces bombarded by fast cluster ions. From key information obtained from a comparison of the electron emissions for insulator KCl and conductor graphite, we concluded that the suppression is predominantly caused by the disturbance of the electron transport by the electric potential generated by moving cluster atoms. The possible shift from suppressed emission to enhanced emission of electrons as cluster speed increases is also discussed in relation to that in the case of cluster stopping power.
- 著者
- Chen Shaoqiang Dierre Benjamin Lee Woong Sekiguchi Takashi Tomita Shigeo Kudo Hiroshi Akimoto Katsuhiro
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.96, no.18, pp.181901, 2010
- 被引用文献数
- 32 12
Erbium-doped GaN with different doping concentrations were grown by ammonia-source molecular beam epitaxy. The intra-4f-shell transitions related green luminescence were observed by both photoluminescence (PL) and cathodoluminescence (CL) measurements. It was found that concentration quenching of Er-related luminescence was observed in PL measurements while not in CL measurements. The different excitation and relaxation processes are suggested as the cause of the concentration quenching characteristics between PL and CL. The strong Er-related CL intensity in highly doped GaN demonstrates that high energy excitation is a promising approach to suppress the concentration quenching in Er-doped GaN.