Magnetization Density Distribution of Sr_{2}IrO_{4} : Deviation from a Local j_{eff}=1/2 Picture
(2020) In Physical Review Letters 125(9). p.97202-97202- Abstract
5d iridium oxides are of huge interest due to the potential for new quantum states driven by strong spin-orbit coupling. The strontium iridate Sr_{2}IrO_{4} is particularly in the spotlight because of the so-called j_{eff}=1/2 state consisting of a quantum superposition of the three local t_{2g} orbitals with, in its simplest version, nearly equal populations, which stabilizes an unconventional Mott insulating state. Here, we report an anisotropic and aspherical magnetization density distribution measured by polarized neutron diffraction in a magnetic field up to 5 T at 4 K, which strongly deviates from a local j_{eff}=1/2 picture even when distortion-induced deviations from the equal weights of the orbital populations are taken into... (More)
5d iridium oxides are of huge interest due to the potential for new quantum states driven by strong spin-orbit coupling. The strontium iridate Sr_{2}IrO_{4} is particularly in the spotlight because of the so-called j_{eff}=1/2 state consisting of a quantum superposition of the three local t_{2g} orbitals with, in its simplest version, nearly equal populations, which stabilizes an unconventional Mott insulating state. Here, we report an anisotropic and aspherical magnetization density distribution measured by polarized neutron diffraction in a magnetic field up to 5 T at 4 K, which strongly deviates from a local j_{eff}=1/2 picture even when distortion-induced deviations from the equal weights of the orbital populations are taken into account. Once reconstructed by the maximum entropy method and multipole expansion model refinement, the magnetization density shows four cross-shaped positive lobes along the crystallographic tetragonal axes with a large spatial extent, showing that the xy orbital contribution is dominant. The analogy to the superconducting copper oxide systems might then be weaker than commonly thought.
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- author
- organization
- publishing date
- 2020-08-28
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review Letters
- volume
- 125
- issue
- 9
- pages
- 1 pages
- publisher
- American Physical Society
- external identifiers
-
- scopus:85090887116
- pmid:32915616
- ISSN
- 1079-7114
- DOI
- 10.1103/PhysRevLett.125.097202
- language
- English
- LU publication?
- yes
- id
- c4c55484-178d-43e6-82f3-7451e88dcf49
- date added to LUP
- 2020-10-19 11:26:15
- date last changed
- 2024-06-26 23:36:11
@article{c4c55484-178d-43e6-82f3-7451e88dcf49,
abstract = {{<p>5d iridium oxides are of huge interest due to the potential for new quantum states driven by strong spin-orbit coupling. The strontium iridate Sr_{2}IrO_{4} is particularly in the spotlight because of the so-called j_{eff}=1/2 state consisting of a quantum superposition of the three local t_{2g} orbitals with, in its simplest version, nearly equal populations, which stabilizes an unconventional Mott insulating state. Here, we report an anisotropic and aspherical magnetization density distribution measured by polarized neutron diffraction in a magnetic field up to 5 T at 4 K, which strongly deviates from a local j_{eff}=1/2 picture even when distortion-induced deviations from the equal weights of the orbital populations are taken into account. Once reconstructed by the maximum entropy method and multipole expansion model refinement, the magnetization density shows four cross-shaped positive lobes along the crystallographic tetragonal axes with a large spatial extent, showing that the xy orbital contribution is dominant. The analogy to the superconducting copper oxide systems might then be weaker than commonly thought.</p>}},
author = {{Jeong, Jaehong and Lenz, Benjamin and Gukasov, Arsen and Fabrèges, Xavier and Sazonov, Andrew and Hutanu, Vladimir and Louat, Alex and Bounoua, Dalila and Martins, Cyril and Biermann, Silke and Brouet, Véronique and Sidis, Yvan and Bourges, Philippe}},
issn = {{1079-7114}},
language = {{eng}},
month = {{08}},
number = {{9}},
pages = {{97202--97202}},
publisher = {{American Physical Society}},
series = {{Physical Review Letters}},
title = {{Magnetization Density Distribution of Sr_{2}IrO_{4} : Deviation from a Local j_{eff}=1/2 Picture}},
url = {{http://dx.doi.org/10.1103/PhysRevLett.125.097202}},
doi = {{10.1103/PhysRevLett.125.097202}},
volume = {{125}},
year = {{2020}},
}