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arXiv · 1111.6284

Raman signatures of pressure induced electronic topological and structural transitions in Bi2Te3

Gopal K. Pradhan·Achintya Bera·Pradeep Kumar·D. V. S. Muthu·A. K. Sood
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Abstract

We report Raman signatures of electronic topological transition (ETT) at 3.6 GPa and rhombohedral (α-Bi2Te3) to monoclinic (β-Bi2Te3) structural transition at ~ 8 GPa. At the onset of ETT, a new Raman mode appears near 107 cm-1 which is dispersionless with pressure. The structural transition at ~ 8 GPa is marked by a change in pressure derivative of A1g and Eg mode frequencies as well as by appearance of new modes near 115 cm-1and 135 cm-1. The mode Grüneisen parameters are determined in both the α and β-phases.

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Gopal K. Pradhan, Achintya Bera, Pradeep Kumar, D. V. S. Muthu, A. K. Sood. 2011-11-27. Raman signatures of pressure induced electronic topological and structural transitions in Bi2Te3. https://doi.org/10.1016/j.ssc.2011.11.029

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