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

Kagome magnets provide a fascinating platform for the realization ofcorrelated topological quantum phases under various magnetic ground states.However, the intricate effect of the magnetic spin configurations on thecharacteristic electronic structure directly from the kagome lattice layerremains still elusive. Here, utilizing angle-resolved photoemissionspectroscopy and density functional theory calculations, we report thespectroscopic evidence for the spin-reorientation effect of a kagomeferromagnet Fe$_3$Ge, which is composed only of the kagome planes. There aretwo kinds of kagome-derived Dirac fermions due to the structuralthree-dimensionality -- one is less dispersive ($k_z$ $\sim$ 0) and the otherdisperses linearly ($k_z$ $\sim$ $\pi$). As the Fe moments cant from the $c$axis into the $ab$ plane upon cooling, the Dirac fermion in $k_z$ $\sim$ 0plane with a mixture of the Fe-$3d_{xy}$ and Fe-$3d_{x^2-y^2}$ componentsevolves from gapped into nearly gapless, while the Dirac cone in $k_z$ $\sim$$\pi$ plane mainly of the Fe-$3d_{x^2-y^2}$ orbital character remains intact,suggesting that the effect of spin reorientation on the Dirac fermions has anorbital selectivity. Our unambiguous observations provide a feasible route todesign and manipulate the mass of Dirac fermions for realizing the novelquantum phases. We also perform comparative studies between thenon-charge-ordered Fe$_3$Ge and its sibling compound FeGe, a newly establishedcharge-density-wave kagome magnet, the results suggest that theorbital-selective van Hove singularities near the Fermi level play anindispensable part in driving the charge order on a magnetic kagome lattice.

Orbital-selective effect of spin reorientation on the Dirac fermions in a three-dimensional kagome ferromagnet Fe$_3$Ge