Enhanced Spin-polarization via Partial Ge1-dimerization as the Driving Force of the 2$\times$2$\times$2 CDW in FeGe
In: Phys. Rev. Materials. 7, 104006 (2023); (2023)
Online
report
A $2\times2\times2$ charge density wave (CDW) was recently observed deep inside the antiferromagnetic phase of a Kagome metal FeGe. A key question is whether the CDW in FeGe is driven by its electronic correlation and magnetism. Here, we address this problem using density functional theory and its combination with $U$ as well as dynamical mean-field theory. Our calculations show that large dimerization ($\sim 1.3 \overset{\lower.5em\circ}{\mathrm{A}}$) of Ge1-sites along $c$-axis will enhance electronic correlation of the Fe-$3d$ orbitals and, as a result, it enhances the spin-polarization and saves more magnetic exchange energies. We find that the balance between magnetic energy saving and structural energy cost via partially dimerizing Ge1-sites in an enlarged superstructure, could induce a new local minimum in total energies. The response to the large partial Ge1-dimerization will induce additional small modulations ($<0.05 \overset{\lower.5em\circ}{\mathrm{A}}$) of other sites in the Kagome and honeycomb layers, which further reduces the total energy and leads to a stable $2\times 2\times 2$ CDW ground state in FeGe. Our results are in good agreement with the existing experiments and reveal a novel CDW mechanism driven by the interplay of structure, electronic correlation and magnetism.
Comment: 4 pages and 4 figures in the main text; 2 pages and 1 figure in the Supplementary Materials
Titel: |
Enhanced Spin-polarization via Partial Ge1-dimerization as the Driving Force of the 2$\times$2$\times$2 CDW in FeGe
|
---|---|
Autor/in / Beteiligte Person: | Wang, Yilin |
Link: | |
Quelle: | Phys. Rev. Materials. 7, 104006 (2023); (2023) |
Veröffentlichung: | 2023 |
Medientyp: | report |
DOI: | 10.1103/PhysRevMaterials.7.104006 |
Schlagwort: |
|
Sonstiges: |
|