Nanoscale modification of electronic states of HOPG by the single impact of HCI

T. Meguro, Y. Yamaguchi, H. Fukagawa, H. Takai, N. Hanano, Y. Yamamoto, K. Kobashi, T. Ishii

Research output: Contribution to journalConference articlepeer-review

14 Citations (Scopus)


Slow Ar8+ impact with 400 eV of kinetic energy upon graphite followed by subsequent electron injection induced the transition from sp 2 to sp3 hybridization, resulting in the formation of a non-conductive region at the metallic graphite surface. From the I-V characteristics measured by scanning tunneling spectroscopy, it was confirmed that the Ar8+ impact region showed an energy gap with ∼6 eV. The impact region was found to work as an electron emitter similar to the CVD-grown poly-crystalline diamond film after the further treatment in hydrogen ambient at 600 °C. It was confirmed from the Raman spectroscopic measurements that vacancies were introduced into the sp2 region by the slow Ar 8+ impact, and also found that the most presumable sp3 cluster model which can explain experimental results had a defective and more planar structure from DV-Xa molecular orbital calculations.


  • Diamond
  • Electronic states
  • Graphite
  • Highly charged ion


Dive into the research topics of 'Nanoscale modification of electronic states of HOPG by the single impact of HCI'. Together they form a unique fingerprint.

Cite this