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arXiv · 2001.04852

EPR spectra and magnetization of XY-type rare-earth ions in pyrochlores Y$_2$Ti$_2$O$_7$:RE$^{3+}$ (RE=Yb, Er)

R. G. Batulin·M. A. Cherosov·I. F. Gilmutdinov·A. G. Kiiamov·V. V. Klekovkina·B. Z. Malkin·A. A. Rodionov·R. V. Yusupov
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Abstract

The results of studies of Y$_{2}$Ti$_2$O$_7$ single crystals doped with Er$^{3+}$ and Yb$^{3+}$ ions by means of electron paramagnetic resonance (EPR) and dc-magnetometry are reported. EPR signals of the trigonal centers with the characteristic hyperfine structure of Er$^{3+}$ or Yb$^{3+}$ ions were observed. Field dependences of magnetization of single crystals for magnetic fields directed along the crystallographic axes and temperature dependences of magnetic susceptibilities were measured. Spin Hamiltonian parameters ($g$-factors and parameters of the hyperfine interaction) for Er$^{3+}$ and Yb$^{3+}$ ions were obtained from analysis of experimental data. The registered EPR spectra and magnetization curves were successfully reproduced by simulations in framework of the crystal-field approach, in particular, with an account for hybridization of ground 4f$^{13}$ configuration of Yb$^{3+}$ ions with the charge transfer states.

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R. G. Batulin, M. A. Cherosov, I. F. Gilmutdinov, A. G. Kiiamov, V. V. Klekovkina, B. Z. Malkin, A. A. Rodionov, R. V. Yusupov. 2020-01-14. EPR spectra and magnetization of XY-type rare-earth ions in pyrochlores Y$_2$Ti$_2$O$_7$:RE$^{3+}$ (RE=Yb, Er). https://doi.org/10.26907/mrsej-19601

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