Pressure induced Superconductivity and location of Fermi energy at Dirac point in BiSbTe3

Vinod K. Gangwar; Shiv Kumar; Mahima Singh; Labanya Ghosh; Zhang Yufeng; Prashant Shahi; Swapnil Patil; Eike F. Schwier; Kenya Shimada; Yoshiya Uwatoko; Sandip Chatterjee

arXiv · 1906.10336

Pressure induced Superconductivity and location of Fermi energy at Dirac point in BiSbTe3

Vinod K. Gangwar·Shiv Kumar·Mahima Singh·Labanya Ghosh·Zhang Yufeng·Prashant Shahi·Swapnil Patil·Eike F. Schwier·Kenya Shimada·Yoshiya Uwatoko·Sandip Chatterjee

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Abstract

We have grown single-crystal BiSbTe3 3D TI sample and studied structural, TE as well as pressure dependent magneto-transport properties. Large positive Seebeck coefficient confirmed the p-type nature of BiSbTe3, which is consistent with Hall measurement. We have also studied the electronic band structure using Laser-based ARPES, which revealed the existence of a Dirac-cone like metallic surface state in BiSbTe3 with a Dirac Point situated exactly at the Fermi level. Additionally, superconductivity emerges under pressure of 8 GPa with a critical temperature of ~2.5 K. With further increase of pressure, the superconducting transition temperature (Tc) increases and at 14 GPa it shows the maximum Tc (~3.3 K).

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Vinod K. Gangwar, Shiv Kumar, Mahima Singh, Labanya Ghosh, Zhang Yufeng, Prashant Shahi, Swapnil Patil, Eike F. Schwier, Kenya Shimada, Yoshiya Uwatoko, Sandip Chatterjee. 2019-06-25. Pressure induced Superconductivity and location of Fermi energy at Dirac point in BiSbTe3. https://arxiv.org/abs/1906.10336

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