The PbGa₂S₄: Tm³⁺ crystal was investigated by tunable high-frequency EPR spectroscopy. Two thulium centers located in positions with different local symmetry were observed in the frequency range of 9.8–170 GHz. Both spectra with the resolved hyperfine structure correspond to the transition between sublevels of the main quasi-doublet Tm³⁺ with crystal field splitting of 6.93 GHz and 1.42 GHz. The times of phase memory and spin-lattice relaxation of thulium ions were measured by the spin-echo method for various values of the magnetic field.

中文翻译：

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PbGa2S4晶体中Tm3+离子的宽带EPR光谱和弛豫研究

PbGa ₂ S ₄ : Tm ³⁺晶体通过可调谐高频EPR光谱进行研究。在 9.8-170 GHz 的频率范围内观察到位于具有不同局部对称性位置的两个铥中心。具有解析超精细结构的两个光谱对应于具有 6.93 GHz 和 1.42 GHz 晶体场分裂的主准双峰 Tm ^{3+ 的}子能级之间的跃迁。铥离子的相位记忆和自旋晶格弛豫时间通过自旋回波法测量不同磁场值。