Spin Dynamics and Light-Induced Effects in EuZn$_2$P$_2$

M. Dutra; G. G. Vasques; P. C. Sabino; J. G. Dias; J. F. Oliveira; M. A. A. Heringer; M. Cabrera-Baez; E. Baggio-Saitovitch; A. R. V. Benvenho; M. A. Avila; J. Munevar

arXiv · 2506.07681

Spin Dynamics and Light-Induced Effects in EuZn$_2$P$_2$

M. Dutra·G. G. Vasques·P. C. Sabino·J. G. Dias·J. F. Oliveira·M. A. A. Heringer·M. Cabrera-Baez·E. Baggio-Saitovitch·A. R. V. Benvenho·M. A. Avila·J. Munevar

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Abstract

The magnetic spin dynamics and optical properties of EuZn$_2$P$_2$ are studied. Single crystals grown by the Sn-flux method crystallize in the $P\overline{3}m1$ (No.~164) space group and order antiferromagnetically at $T_N=23.5$~K. $^{151}$Eu M\"ossbauer spectroscopy confirms the presence of the Eu$^{2+}$ oxidation state only and the magnetic moment angle relative to the $c$-axis is $\theta=46(3)$\textdegree. Temperature-dependent electron spin resonance (ESR) measurements reveal that spin-spin interactions predominantly govern the spin relaxation mechanisms, as evidenced by the linewidth behavior ($\Delta H$). Positive $g$-shifts ($\Delta g)$ for $H \parallel ab$ indicate the presence of local electron polarization. The ESR data support the formation of anisotropic magnetic polarons, which trap spin carriers and contribute to increased electrical resistance. Angular-dependent ESR spectra at room temperature display anisotropic behavior in both $\Delta g(\phi)$ and $\Delta H(\phi)$, with a dominant three-dimensional component $C_{3D}$, indicative of robust interlayer coupling and antiferromagnetic fluctuations. Under light illumination, a small broadening of $\Delta H$ is observed. Furthermore, a photovoltaic effect is identified in EuZn$_2$P$_2$, with photodetector performance metrics suggesting promising capabilities for future optoelectronic devices.

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M. Dutra, G. G. Vasques, P. C. Sabino, J. G. Dias, J. F. Oliveira, M. A. A. Heringer, M. Cabrera-Baez, E. Baggio-Saitovitch, A. R. V. Benvenho, M. A. Avila, J. Munevar. 2025-06-09. Spin Dynamics and Light-Induced Effects in EuZn$_2$P$_2$. https://arxiv.org/abs/2506.07681

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