Extinction of ferromagnetism in highly ordered pyrolytic graphite by annealing

Xiaochang Miao, Sefaattin Tongay, Arthur F. Hebard

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We report that the ferromagnetism of highly ordered pyrolytic graphite (HOPG) samples as measured by hysteretic magnetization loops can be diminished and eventually extinguished with sufficiently long high vacuum anneals at temperatures on the order of 2300 °C. Concomitant with the extinction of ferromagnetism, we observe an anneal-induced increase in grain size (accompanied by possible edge reconstruction) confirmed by X-ray diffraction measurements and improved transport properties, including lower in-plane and out-of-plane resistivity, higher electron and hole mobility and improved charge compensation. The implied reduction of defects and vacancies by annealing suggests that the ferromagnetism of pristine HOPG is correlated with localized states located at zigzag edges, vacancies and related defects.

Original languageEnglish (US)
Pages (from-to)1614-1618
Number of pages5
JournalCarbon
Volume50
Issue number4
DOIs
StatePublished - Apr 2012
Externally publishedYes

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Ferromagnetism
Annealing
Vacancies
Defects
Hole mobility
Electron mobility
Transport properties
Magnetization
Vacuum
X ray diffraction
Temperature

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Extinction of ferromagnetism in highly ordered pyrolytic graphite by annealing. / Miao, Xiaochang; Tongay, Sefaattin; Hebard, Arthur F.

In: Carbon, Vol. 50, No. 4, 04.2012, p. 1614-1618.

Research output: Contribution to journalArticle

Miao, Xiaochang ; Tongay, Sefaattin ; Hebard, Arthur F. / Extinction of ferromagnetism in highly ordered pyrolytic graphite by annealing. In: Carbon. 2012 ; Vol. 50, No. 4. pp. 1614-1618.
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