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arXiv · 2410.13715

Electronic Raman scattering of antiferromagnetic excitonic insulators

Hidemaro Suwa·Shang-Shun Zhang·Cristian D. Batista
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Abstract

The excitonic insulator, a quantum mechanical state arising from exciton condensation, was proposed theoretically many years ago but has yet to be experimentally confirmed. The discovery of correlated transition metal oxides based on $4d$ and $5d$ elements, where the on-site Coulomb repulsion is comparable to the dominant hopping amplitude, presents a unique opportunity to study exciton condensation. By constructing an effective mean field Raman operator for the Hubbard model, we derive the low-energy electronic Raman scattering cross section, demonstrating Raman spectroscopy as a powerful tool for detecting exciton condensation. Here, we demonstrate that Raman scattering directly reveals exciton condensation in the bilayer iridate Sr$_3$Ir$_2$O$_7$ under pressure.

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Hidemaro Suwa, Shang-Shun Zhang, Cristian D. Batista. 2024-10-17. Electronic Raman scattering of antiferromagnetic excitonic insulators. https://arxiv.org/abs/2410.13715

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