Vacancies and vacancy clusters produced by carbon ion implantation in highly

oriented pyrolytic graphite, and their annealing behaviour associated with the

ferromagnetism of the implanted sample were studied using positron annihilation

in conjunction with ferromagnetic moment measurements using a superconducting

quantum interferometer device magnetometer. The results indicate that the

magnetic moments were closely correlated to the existence of the vacancy defects

in the samples and this was supported by theoretical calculations using density

functional theory. The mechanism of magnetic order in the implanted sample was

discussed.

Correlation Between the Vacancy Defects and Ferromagnetism in Graphite.

X.Yang, H.Xia, X.Qin, W.Li, Y.Dai, X.Liu, M.Zhao, Y.Xia, S.Yan, B.Wang:

Carbon, 2009, 47[5], 1399-406