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arXiv · 2105.03479

Magnetic properties of the itinerant ferromagnet LaCrGe3 under pressure studied by 139La NMR

K. Rana·H. Kotegawa·R. R. Ullah·E. Gati·S. L. Bud'ko·P. C. Canfield·H. Tou·V. Taufour·Y. Furukawa
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Abstract

$^{139}$La nuclear magnetic resonance (NMR) measurements under pressure ($p = 0-2.64$ GPa) have been carried out to investigate the static and dynamic magnetic properties of the itinerant ferromagnet LaCrGe$_3$. $^{139}$La-NMR spectra for all measured pressures in the ferromagnetically ordered state show a large shift due to the internal field induction $|$$B_{\rm int}$$|$ $\sim$ 4 T at the La site produced by Cr ordered moments. The change in $B_{\rm int}$ by less than 5\% with $p$ up to 2.64~GPa indicates that the Cr 3$d$ moments are robust under pressure. The temperature dependence of NMR shift and $B_{\rm int}$ suggest that the ferromagnetic order develops below $\sim$ 50~K under higher pressures in a magnetic field of $\sim$ 7.2 T. Based on the analysis of NMR data using the self-consistent-renormalization (SCR) theory, the spin fluctuations in the paramagnetic state well above $T_{\rm C}$ are revealed to be three dimensional ferromagnetic throughout the measured $p$ region.

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K. Rana, H. Kotegawa, R. R. Ullah, E. Gati, S. L. Bud'ko, P. C. Canfield, H. Tou, V. Taufour, Y. Furukawa. 2021-05-07. Magnetic properties of the itinerant ferromagnet LaCrGe3 under pressure studied by 139La NMR. https://doi.org/10.1103/physrevb.103.174426

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