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arXiv · 2005.01269

Preparation, Characterization and electronic structure of Ti-doped Bi$_2$Se$_3$

Sawani Datta·Arindam Pramanik·Ram Prakash Pandeya·Anup Pradhan Sakhya·A. Thamizhavel·Kalobaran Maiti
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Abstract

We report the preparation of high-quality single crystal of Bi$_2$Se$_3$, a well-known topological insulator and its Ti-doped compositions using Bridgeman technique. Prepared single crystals were characterized by x-ray diffraction (XRD) to check the crystalline structure and energy dispersive analysis of x-rays for composition analysis. The XRD data of Ti-doped compounds show a small shift with respect to normal Bi$_2$Se$_3$ indicating changes in the lattice parameters while the structure type remained unchanged; this also establishes that Ti goes to the intended substitution sites. All the above analysis establishes successful preparation of these crystals with high quality using Bridgman technique. We carried out x-ray photo-emission spectroscopy to study the composition via investigating the core level spectra. Bi$_2$Se$_3$ spectra exhibit sharp and distinct features for the core levels and absence of impurity features. The core level spectra of the Ti-doped sample exhibit distinct signal due to Ti core levels. The analysis of the spectral features reveal signature of plasmon excitation and final state satellites; a signature of finite electron correlation effect in the electronic structure.

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Sawani Datta, Arindam Pramanik, Ram Prakash Pandeya, Anup Pradhan Sakhya, A. Thamizhavel, Kalobaran Maiti. 2020-05-04. Preparation, Characterization and electronic structure of Ti-doped Bi$_2$Se$_3$. https://doi.org/10.1063/5.0017185

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