Direct visualization of dipolar ferromagnetic domain structures in Co nanoparticle monolayers by electron holography

Kazuo Yamamoto, Sara A. Majetich, Martha McCartney, Madhur Sachan, Saeki Yamamuro, Tsukasa Hirayama

Research output: Contribution to journalArticle

42 Scopus citations


Electron holography has revealed dipolar ferromagnetic domain structures in ordered monolayer arrays of Co nanoparticles. In zero-field-cooling experiments, we demonstrate the formation of micron-sized magnetically ordered regions with transverse domain walls, and a spatially varying moment order parameter. Truncated vortex structures that can be modified by an applied field are observed near the sample edges. The collectively magnetized state shows soft magnetic properties and long-range order that is stable over times over 1 h at 108 K.

Original languageEnglish (US)
Article number082502
JournalApplied Physics Letters
Issue number8
StatePublished - Sep 15 2008


ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

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