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arXiv · 2401.17407

Magneto-synthesis effect on magnetic order, phonons, and magnons in single-crystal Sr$_2$IrO$_4$

Nicholas Pellatz·Jungho Kim·Jong-Woo Kim·Itamar Kimchi·Gang Cao·Dmitry Reznik
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Abstract

It was shown earlier that applying a magnetic field during the growth of Sr$_2$IrO$_4$, also known as "field-alteration", induces significant changes to its structural, magnetic, and transport properties. However, the microscopic nature of these changes is enigmatic. In this study, we employed resonant elastic and inelastic x-ray scattering, as well as Raman scattering, to investigate samples from two batches of Sr$_2$IrO$_4$ grown in magnetic fields of different strengths. Our findings reveal that samples grown in a weaker magnetic field have similar magnetic order to non-altered samples, whereas those grown in a stronger field show a different stacking of weak in-plane ferromagnetic moments. Additionally, we observed significant softening and broadening of select Raman-active phonons in the field altered samples, with a stronger effect in the samples grown in the stronger field. We discuss insights that our results provide into the microscopic nature of field-alteration in Sr$_2$IrO$_4$.

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Nicholas Pellatz, Jungho Kim, Jong-Woo Kim, Itamar Kimchi, Gang Cao, Dmitry Reznik. 2024-01-30. Magneto-synthesis effect on magnetic order, phonons, and magnons in single-crystal Sr$_2$IrO$_4$. https://doi.org/10.1103/physrevmaterials.7.123802

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