تقرير
Quasimolecular electronic structure of the spin-liquid candidate Ba$_3$InIr$_2$O$_9$
| العنوان: | Quasimolecular electronic structure of the spin-liquid candidate Ba$_3$InIr$_2$O$_9$ |
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| المؤلفون: | Revelli, A., Sala, M. Moretti, Monaco, G., Magnaterra, M., Attig, J., Peterlini, L., Dey, T., Tsirlin, A. A., Gegenwart, P., Fröhlich, T., Braden, M., Grams, C., Hemberger, J., Becker, P., van Loosdrecht, P. H. M., Khomskii, D. I., Brink, J. van den, Hermanns, M., Grüninger, M. |
| المصدر: | Phys. Rev. B 106, 155107 (2022) |
| سنة النشر: | 2022 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Strongly Correlated Electrons |
| الوصف: | The mixed-valent iridate Ba3InIr2O9 has been discussed as a promising candidate for quantum spin-liquid behavior. The compound exhibits Ir$^{4.5+}$ ions in face-sharing IrO6 octahedra forming Ir2O9 dimers with three t2g holes per dimer. Our results establish Ba3InIr2O9 as a cluster Mott insulator. Strong intra-dimer hopping delocalizes the three t2g holes in quasi-molecular dimer states while inter-dimer charge fluctuations are suppressed by Coulomb repulsion. The magnetism of Ba3InIr2O9 emerges from spin-orbit entangled quasi-molecular moments with yet unexplored interactions, opening up a new route to unconventional magnetic properties of 5d compounds. Using single-crystal x-ray diffraction we find the monoclinic space group C2/c already at room temperature. Dielectric spectroscopy shows insulating behavior. Resonant inelastic x-ray scattering (RIXS) reveals a rich excitation spectrum below 1.5 eV with a sinusoidal dynamical structure factor that unambiguously demonstrates the quasi-molecular character of the electronic states. Below 0.3 eV, we observe a series of excitations. According to exact diagonalization calculations, such low-energy excitations reflect the proximity of Ba3InIr2O9 to a hopping-induced phase transition based on the condensation of a quasi-molecular spin-orbit exciton. The dimer ground state roughly hosts two holes in a bonding j=1/2 orbital and the third hole in a bonding j=3/2 orbital. Comment: 14 pages, 10 figures, V2: published version, minor changes |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1103/PhysRevB.106.155107 |
| URL الوصول: | http://arxiv.org/abs/2207.04795 |
| رقم الأكسشن: | edsarx.2207.04795 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1103/PhysRevB.106.155107 |
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