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arXiv · 1902.11172

Magnetic structure and spin waves in the frustrated ferro-antiferromagnet Pb$_2$VO(PO$_4$)$_2$

Simon Bettler·Florian Landolt·Ömer M. Aksoy·Zewu Yan·Severian Gvasaliya·Yiming Qiu·Eric Ressouche·Ketty Beauvois·Stéphane Raymond·Alexey N. Ponomaryov·Sergei A. Zvyagin·Andrey Zheludev
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Abstract

Single crystal neutron diffraction, inelastic neutron scattering and electron spin resonance experiments are used to study the magnetic structure and spin waves in Pb$_2$VO(PO$_4$)$_2$, a prototypical layered $S=1/2$ ferromagnet with frustrating next nearest neighbor antiferromagnetic interactions. The observed excitation spectrum is found to be inconsistent with a simple square lattice model previously proposed for this material. At least four distinct exchange coupling constants are required to reproduce the measured spin wave dispersion. The degree of magnetic frustration is correspondingly revised and found to be substantially smaller than in all previous estimates.

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Simon Bettler, Florian Landolt, Ömer M. Aksoy, Zewu Yan, Severian Gvasaliya, Yiming Qiu, Eric Ressouche, Ketty Beauvois, Stéphane Raymond, Alexey N. Ponomaryov, Sergei A. Zvyagin, Andrey Zheludev. 2020-03-11. Magnetic structure and spin waves in the frustrated ferro-antiferromagnet Pb$_2$VO(PO$_4$)$_2$. https://doi.org/10.1103/physrevb.99.184437

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