Magnetism and electronic dynamics in $CuCr_{2-x}Sn_xS_4$ spinels studied by transferred hyperfine fields at $^{119}Sn$ and muon spin rotation and relaxation

Elaheh Sadrollahi; Cynthia P. C. Medrano; Magno A. V. Heringer; E. M. Baggio Saitovitch; Lilian Prodan; Vladimir Tsurkan; F. Jochen Litterst

arXiv · 2501.05151

Magnetism and electronic dynamics in $CuCr_{2-x}Sn_xS_4$ spinels studied by transferred hyperfine fields at $^{119}Sn$ and muon spin rotation and relaxation

Elaheh Sadrollahi·Cynthia P. C. Medrano·Magno A. V. Heringer·E. M. Baggio Saitovitch·Lilian Prodan·Vladimir Tsurkan·F. Jochen Litterst

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Abstract

We investigated magnetization, muon spin rotation ($\mu$SR), and $^{119}Sn$ M\"{o}ssbauer spectroscopy on Sn substituted $CuCr_{2-x}Sn_xS_4$ (x=0.03 and 0.08) spinel compounds. The magnetization and $\mu$SR results reveal similar additional low-temperature magnetic transitions around 80 K and 40 K as found for the undoped material, indicating a magnetic ground state deviating from a simple collinear ferromagnet. The observed changes in the M\"{o}ssbauer hyperfine spectra are less pronounced and are discussed in view of the different positions of the local probes $\mu^+$ and $^{119}Sn$ and their different magnetic coupling to the magnetic Cr lattice. Above 80 K, both $\mu$SR and M\"{o}ssbauer spectra show temperature-dependent inhomogeneous broadening either due to structural or charge disorder and changing spin dynamics that can be related to a precursor magnetic phase above the well-defined static low-temperature phase.

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Elaheh Sadrollahi, Cynthia P. C. Medrano, Magno A. V. Heringer, E. M. Baggio Saitovitch, Lilian Prodan, Vladimir Tsurkan, F. Jochen Litterst. 2025-01-09. Magnetism and electronic dynamics in $CuCr_{2-x}Sn_xS_4$ spinels studied by transferred hyperfine fields at $^{119}Sn$ and muon spin rotation and relaxation. https://arxiv.org/abs/2501.05151

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