Spin-orbit excitons in a correlated metal: Raman scattering study of Sr2RhO4

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Wang, Lichen, Liu, Huimei, Zimmermann, Valentin, Yogi, Arvind Kumar, Isobe, Masahiko, Minola, Matteo, Hepting, Matthias, Khaliullin, Giniyat, Keimer, Bernhard
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929281779630080
author Wang, Lichen
Liu, Huimei
Zimmermann, Valentin
Yogi, Arvind Kumar
Isobe, Masahiko
Minola, Matteo
Hepting, Matthias
Khaliullin, Giniyat
Keimer, Bernhard
author_facet Wang, Lichen
Liu, Huimei
Zimmermann, Valentin
Yogi, Arvind Kumar
Isobe, Masahiko
Minola, Matteo
Hepting, Matthias
Khaliullin, Giniyat
Keimer, Bernhard
contents Using Raman spectroscopy to study the correlated 4$d$-electron metal Sr$_2$RhO$_4$, we observe pronounced excitations at 220 meV and 240 meV with $A_\mathrm{1g}$ and $B_\mathrm{1g}$ symmetries, respectively. We identify them as transitions between the spin-orbit multiplets of the Rh ions, in close analogy to the spin-orbit excitons in the Mott insulators Sr$_2$IrO$_4$ and $α$-RuCl$_3$. This observation provides direct evidence for the unquenched spin-orbit coupling in Sr$_2$RhO$_4$. A quantitative analysis of the data reveals that the tetragonal crystal field $Δ$ in Sr$_2$RhO$_4$ has a sign opposite to that in insulating Sr$_2$IrO$_4$, which enhances the planar $xy$ orbital character of the effective $J=1/2$ wave function. This supports a metallic ground state, and suggests that $c$-axis compression of Sr$_2$RhO$_4$ may transform it into a quasi-two-dimensional antiferromagnetic insulator.
format Preprint
id arxiv_https___arxiv_org_abs_2309_15299
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Spin-orbit excitons in a correlated metal: Raman scattering study of Sr2RhO4
Wang, Lichen
Liu, Huimei
Zimmermann, Valentin
Yogi, Arvind Kumar
Isobe, Masahiko
Minola, Matteo
Hepting, Matthias
Khaliullin, Giniyat
Keimer, Bernhard
Strongly Correlated Electrons
Using Raman spectroscopy to study the correlated 4$d$-electron metal Sr$_2$RhO$_4$, we observe pronounced excitations at 220 meV and 240 meV with $A_\mathrm{1g}$ and $B_\mathrm{1g}$ symmetries, respectively. We identify them as transitions between the spin-orbit multiplets of the Rh ions, in close analogy to the spin-orbit excitons in the Mott insulators Sr$_2$IrO$_4$ and $α$-RuCl$_3$. This observation provides direct evidence for the unquenched spin-orbit coupling in Sr$_2$RhO$_4$. A quantitative analysis of the data reveals that the tetragonal crystal field $Δ$ in Sr$_2$RhO$_4$ has a sign opposite to that in insulating Sr$_2$IrO$_4$, which enhances the planar $xy$ orbital character of the effective $J=1/2$ wave function. This supports a metallic ground state, and suggests that $c$-axis compression of Sr$_2$RhO$_4$ may transform it into a quasi-two-dimensional antiferromagnetic insulator.
title Spin-orbit excitons in a correlated metal: Raman scattering study of Sr2RhO4
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2309.15299