Lattice Symmetry Breaking and Ascending in Magnetic Kagome Metal

April 26, 2024
a) – c) Crystal structures of FeGe at different temperatures. d) Δd/d as a function of temperature measured using Larmor diffraction for (0,2,0) , (2,0,0), and (2,−2,0) nuclear Bragg peaks. Each peak is separated by 120 degrees in the ab plane. The lattice contracts anisotropically along the three directions below ~TN but becomes more isotropic along the [2,0,0] and [0,2,0] directions below ~TCDW.

Scientific Achievement

Larmor diffraction and Raman spectroscopy measurements show that the kagome metal FeGe exhibits unusual lattice symmetry breaking and ascending on cooling.


Significance and Impact

Ultra high momentum resolution Larmor diffraction measurements provide new avenue to understand the interplay between spin, lattice, and charge degrees of freedom.


Research Details

•P3-type Na2/3Cu1/3Mn2/3O2 structure was determined by combining high resolution neutron diffraction, X-ray diffraction, neutron pair distribution function and transmission electron microscope.
•In-situ hard X-ray absorption and ex-situ soft X-ray absorption spectrum, along with density function theory calculations, reveal two distinct charge compensation mechanisms at different voltage plateaus.

Symmetry Breaking and Ascending in the Magnetic Kagome Metal FeGe
Phys. Rev. X 14, 011043 (2024).