We report first observation of electron spin resonance of the bulk charge carriers in 3D topological insulator Bi_1.08Sn_0.02Sb_0.9Te₂S. The observed spectra represent the overlay of two different signals from electrons and holes with the g-factors enormously enhanced due to strong spin-orbit coupling typical for topological insulators. The analysis of the ESR lines indicates that the current carriers responsible for the resonance may be organized in nanosize electron and hole droplets. It is not excluded that such droplets when residing near the surface may give rise to nonzero back scattering of surface current carriers.

中文翻译：

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电荷载流子的ESR表明Bi 1.08 Sn 0.02 Sb 0.9 Te 2 S拓扑绝缘子的不均匀体积状态

我们首次报告了3D拓扑绝缘体Bi _1.08 Sn _0.02 Sb _0.9 Te ₂ S中的体电荷载流子的电子自旋共振。观察到的光谱表示来自电子和空穴的两种不同信号的叠加，其g因子极大地增强了拓扑绝缘体典型的强自旋轨道耦合。对ESR谱线的分析表明，负责共振的载流子可以组织成纳米级电子和空穴液滴。不排除这样的液滴在靠近表面时会引起表面载流子的非零反向散射。