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arXiv · 1910.01605

Photoemission Spectrum of Ca2RuO4: Spin Polaron Physics in an S=1 Antiferromagnet with Anisotropies

Adam Kłosiński·Dmitri V. Efremov·Jeroen van den Brink·Krzysztof Wohlfeld
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Abstract

We derive an S=1 spin polaron model which describes the motion of a single hole introduced into the S=1 spin antiferromagnetic ground state of Ca2RuO4. We solve the model using the self-consistent Born approximation and show that its hole spectral function qualitatively agrees with the experimentally observed high-binding energy part of the Ca2RuO4 photoemission spectrum. We explain the observed peculiarities of the photoemission spectrum by linking them to two anisotropies present in the employed model---the spin anisotropy and the hopping anisotropy. We verify that these anisotropies, and not the possible differences between the ruthenate (S=1) and the cuprate (S=1/2) spin polaron models, are responsible for the strong qualitative differences between the photoemission spectrum of Ca2RuO4 and of the undoped cuprates.

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Adam Kłosiński, Dmitri V. Efremov, Jeroen van den Brink, Krzysztof Wohlfeld. 2019-10-03. Photoemission Spectrum of Ca2RuO4: Spin Polaron Physics in an S=1 Antiferromagnet with Anisotropies. https://doi.org/10.1103/physrevb.101.035115

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