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arXiv · 2002.02415

Correlated motion of particle-hole excitations across the renormalized spin-orbit gap in $\rm Sr_2 Ir O_4$

Shubhajyoti Mohapatra·Avinash Singh
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Abstract

The high-energy collective modes of particle-hole excitations across the spin-orbit gap in $\rm Sr_2IrO_4$ are investigated using the transformed Coulomb interaction terms in the pseudo-spin-orbital basis constituted by the $J=1/2$ and $3/2$ states arising from spin-orbit coupling. With appropriate interaction strengths and renormalized spin-orbit gap, these collective modes yield two well-defined propagating spin-orbit exciton modes, with energy scale and dispersion in excellent agreement with resonant inelastic X-ray scattering (RIXS) measurements.

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Shubhajyoti Mohapatra, Avinash Singh. 2020-02-05. Correlated motion of particle-hole excitations across the renormalized spin-orbit gap in $\rm Sr_2 Ir O_4$. https://doi.org/10.1016/j.jmmm.2020.166997

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