Abundant lattice instability in kagome metal ScV$_6$Sn$_6$

Hengxin Tan; Binghai Yan

doi:10.1103/PhysRevLett.130.266402

paper

Abundant lattice instability in kagome metal ScV $_{6}$ Sn $_{6}$

arXiv:2302.07922 · doi:10.1103/PhysRevLett.130.266402

Abstract

Kagome materials are emerging platforms for studying charge and spin orders. In this work, we have revealed a rich lattice instability in a $Z_{2}$ kagome metal ScV $_{6}$ Sn $_{6}$ by first-principles calculations. Beyond verifying the $3 \times 3 \times 3$ charge density wave (CDW) order observed by the recent experiment, we further identified three more possible CDW structures, i.e., $3 \times 3 \times 2$ CDW with $P 6/ mmm$ symmetry, $2 \times 2 \times 2$ CDW with $I mmm$ symmetry, and $2 \times 2 \times 2$ CDW with $P 6/ mmm$ symmetry. The former two are more energetically favored than the $3 \times 3 \times 3$ phase, while the third one is comparable in energy. These CDW distortions involve mainly out-of-plane motions of Sc and Sn atoms, while V atoms constituting the kagome net are almost unchanged. We attribute the lattice instability to the smallness of Sc atomic radius. In contrast, such an instability disappears in its sister compounds $R$ V $_{6}$ Sn $_{6}$ ( $R$ is Y, or a rare-earth element) because $R$ has a larger radius. Our work indicates that ScV $_{6}$ Sn $_{6}$ might exhibit varied CDW phases in different experimental conditions and provides insights to explore rich charge orders in kagome materials.

5 main pages + 4 figures. Supplementary available

Abundant lattice instability in kagome metal ScV $_{6}$ Sn $_{6}$

Abstract

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Cited by in corpus (43)

Abundant lattice instability in kagome metal ScV6​Sn6​

Abstract

References in corpus (40)

Cited by in corpus (43)

Abundant lattice instability in kagome metal ScV $_{6}$ Sn $_{6}$