Nuclear resonant scattering from 193Ir as a probe of the electronic and magnetic properties of iridates

Pavel Alexeev; Olaf Leupold; Ilya Sergueev; Marcus Herlitschke; Desmond McMorrow; R. S. Perry; E. C. Hunter; Ralf Röhlsberger; Hans-Christian Wille

arXiv · 1804.06708

Nuclear resonant scattering from 193Ir as a probe of the electronic and magnetic properties of iridates

Pavel Alexeev·Olaf Leupold·Ilya Sergueev·Marcus Herlitschke·Desmond McMorrow·R. S. Perry·E. C. Hunter·Ralf Röhlsberger·Hans-Christian Wille

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Abstract

The high brilliance of the modern synchrotron radiation sources facilitates experiments with high energy x-rays. In this Letter we report on Nuclear Resonance Scattering at the 73 keV nuclear level in 193Ir. The transitions between the hyperfine split levels show an exceptionally large E2/M1 multi-polarity mixing ratio combined with an increased sensitivity to certain changes in the hyperfine field direction compared to non-mixing transitions. The method opens a new way for probing local magnetic and electronic properties of correlated materials containing iridium and provides novel insights into their anisotropic magnetism. In particular, unexpected out-of-plane components of magnetic hyperfine fields and non-zero electric field gradients in Sr2IrO4 have been detected and attributed to the presence of strong spin-orbit interaction. Due to the high, 62% natural abundance of the 193Ir isotope, no isotopic enrichment of the samples is required, qualifying the method for a broad range of applications.

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Pavel Alexeev, Olaf Leupold, Ilya Sergueev, Marcus Herlitschke, Desmond McMorrow, R. S. Perry, E. C. Hunter, Ralf Röhlsberger, Hans-Christian Wille. 2018-04-18. Nuclear resonant scattering from 193Ir as a probe of the electronic and magnetic properties of iridates. https://arxiv.org/abs/1804.06708

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