Semiconductor Physics, Quantum Electronics & Optoelectronics, 28 (3), P. 329–334 (2025).
DOI: https://doi.org/10.15407/spqeo28.03.329

EPR evidence of paramagnetic to spin glass transition in Zn_1-xMn_xSe:Fe²⁺ single crystals

A.V. Uriadov¹, I.V. Ivanchenko², N.A. Popenko², B.E. Bekirov², E.N. Kalabukhova³, V.M. Tkach⁴, D.V. Savchenko<sup>1,5,*

1</sup>National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, 37, prosp. Beresteiskyi, 03056 Kyiv, Ukraine
²O. Usikov Institute for Radiophysics and Electronics, NAS of Ukraine, 12, Proskura str., 61085 Kharkiv, Ukraine
³V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, prosp. Nauky, 03028 Kyiv, Ukraine
⁴V. Bakul Institute for Superhard Materials, NAS of Ukraine, 2, Avtozavodskaya str., 04074 Kyiv, Ukraine
⁵Technical Center NAS of Ukraine, 13 Pokrovs’ka str., 04070 Kyiv, Ukraine
*Corresponding author e-mail: dariyasavchenko@gmail.com

Abstract. In this work, the paramagnetic-to-spin glass transition in Zn_1–xMn_xSe:Fe²⁺ single crystals by using the analysis of temperature-dependent electron paramagnetic resonance (EPR) spectra were investigated. The transition is characterized by the broadening and a decrease in the amplitude of a single Lorentzian resonance line at g ~ 2.01, with critical freezing temperatures T_f at approximately 5.7 K for x = 0.2 and 8.0 K for x = 0.3. At lower temperatures, EPR spectra reveal three distinct paramagnetic centers attributed to Fe3+ ions at g ~ 4.3, strongly interacting Fe ions at g ~ 2.05, and a vacancy-type center at g ~ 2.003. These results indicate that iron doping promotes Mn clustering and stabilizes the spin glass phase, affecting the magnetic properties of Zn1–xMnxSe.

Keywords: EPR, iron, zinc manganese selenide, spin glass transition.