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Neutron Scattering Study of the kagome metal Sc3Mn3Al7Si5
Sc 3 Mn 3 Al 7 Si 5 is a rare example of a correlated metal in which the Mn moments form a kagome lattice. The absence of magnetic ordering to the lowest temperatures suggests that geometrical frustration of magnetic interactions may lead to strong magnetic fluctuations. We have performed inelastic neutron scattering measurements on Sc 3 Mn 3 Al 7 Si 5 , finding that phonon scattering dominates for energies from ∼20–50 meV. These results are in good agreement with ab initio calculations of the phonon dispersions and densities of states, and as well reproduce the measured specific heat. A weak magnetic signal was detected at energies less than ∼10 meV, present only at the lowest temperatures. The magnetic signal is broad and quasielastic, as expected for metallic paramagnets.
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Publication Date:
NSF-PAR ID:
10299911
Journal Name:
Physical review
Volume:
104
Page Range or eLocation-ID:
134305
ISSN:
2470-0010
Sponsoring Org:
National Science Foundation
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