English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The role of self-intercalation in 2D van der Waals materials is key to theunderstanding of many of their properties. Here we show that the magneticordering temperature of thin films of the 2D ferromagnet Fe5GeTe2 issubstantially increased by self-intercalated Fe that resides in the van derWaals gaps. The epitaxial films were prepared by molecular beam epitaxy andtheir magnetic properties explored by element-specific x-ray magnetic circulardichroism that showed ferromagnetic ordering up to 375 K. Both surface and bulksensitive x-ray absorption modes were used to confirm that the magnetic signalis of an intrinsic nature. Fe occupation within the van der Waals gaps wasdetermined by high-precision x-ray diffraction analysis which showed a notablyhigher Fe occupation than in bulk crystals. We thus infer that the highermagnetic ordering temperature results from an increased exchange interactionamong the Fe5GeTe2 layers mediated by iron within the gaps between theselayers. Our findings establish self-intercalation during epitaxial growth as anefficient mechanism to achieve high-temperature magnetism in a broad class ofvan der Waals materials.

Self-intercalation as origin of high-temperature ferromagnetism in epitaxially grown Fe5GeTe2 thin films