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arXiv · 2008.12921

A $j_\mathrm{eff} = 1/2$ pseudospinon continuum in CaIrO$_3$

Matteo Rossi·Pietro Marabotti·Yasuyuki Hirata·Giulio Monaco·Michael Krisch·Kenya Ohgushi·Krzysztof Wohlfeld·Jeroen van den Brink·Marco Moretti Sala
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Abstract

In so-called $j_\mathrm{eff} = 1/2$ systems, including some iridates and ruthenates, the coherent superposition of $t_\mathrm{2g}$ orbitals in the ground state gives rise to hopping processes that strongly depend on the bond geometry. Resonant inelastic x-ray scattering (RIXS) measurements on CaIrO$_3$ reveal a prototypical $j_\mathrm{eff} = 1/2$ pseudospinon continuum, a hallmark of one-dimensional (1D) magnetic systems despite its three-dimensional crystal structure. The experimental spectra compare very well to the calculated magnetic dynamical structure factor of weakly coupled spin-1/2 chains. We attribute the onset of such quasi-1D magnetism to the fundamental difference in the magnetic interactions between the $j_\mathrm{eff} = 1/2$ pseudospins along the corner- and edge-sharing bonds in CaIrO$_3$.

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Matteo Rossi, Pietro Marabotti, Yasuyuki Hirata, Giulio Monaco, Michael Krisch, Kenya Ohgushi, Krzysztof Wohlfeld, Jeroen van den Brink, Marco Moretti Sala. 2020-08-29. A $j_\mathrm{eff} = 1/2$ pseudospinon continuum in CaIrO$_3$. https://doi.org/10.1140/epjp/s13360-020-00649-5

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