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Electrical, Thermal and Spectroscopic Characterization of Bulk Bi2Se3 Topological Insulator
Rabia Sultana,Geet Awana,Geet Awana,Banabir Pal,P. K. Maheshwari,Monu Mishra,Govind Gupta,Anurag Gupta,Setti Thirupathaiah,V.P.S. Awana +9 more
TLDR
In this paper, the authors reported electrical properties of Bi2Se3 topological insulator, which is being grown by self flux method through solid state reaction from high temperature (950C) melt and slow cooling of constituent elements.Abstract:
We report electrical (angular magneto-resistance, and Hall), thermal (heat capacity) and spectroscopic (Raman, x-ray photo electron, angle resolved photo electron) characterization of bulk Bi2Se3 topological insulator, which is being is grown by self flux method through solid state reaction from high temperature (950C) melt and slow cooling (2C/hour) of constituent elements. Bi2Se3 exhibited metallic behaviour down to 5K. Magneto transport measurements revealed linear up to 400% and 30% MR at 5K under 14 Tesla field in perpendicular and parallel field direction respectively. We noticed that the magneto-resistance (MR) of Bi2Se3 is very sensitive to the angle of applied field. MR is maximum when the field is normal to the sample surface, while it is minimum when the field is parallel. Hall coefficient (RH) is seen nearly invariant with negative carrier sign down to 5K albeit having near periodic oscillations above 100K. Heat capacity (Cp) versus temperature plot is seen without any phase transitions down to 5K and is well fitted (Cp = gammaT + betaT3) at low temperature with calculated Debye temperature (ThetaD) value of 105.5K. Clear Raman peaks are seen at 72, 131 and 177 cm-1 corresponding to A1g1, Eg2 and A1g2 respectively. Though, two distinct asymmetric characteristic peak shapes are seen for Bi 4f7/2 and Bi 4f5/2, the Se 3d region is found to be broad displaying the overlapping of spin - orbit components of the same. Angle-resolved photoemission spectroscopy (ARPES) data of Bi2Se3 revealed distinctly the bulk conduction bands (BCB), surface state (SS), Dirac point (DP) and bulk valence bands (BVB) and 3D bulk conduction signatures are clearly seen. Summarily, host of physical properties for as grown Bi2Se3 crystal are reported here.read more
Citations
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Journal ArticleDOI
Crystal growth and characterization of bulk Sb2Te3 topological insulator
TL;DR: In this article, the Sb2Te3 topological insulator is grown using self flux method via solid state reaction route, by melting constituent elements (Sb and Te) at high temperature (850 °C), followed by slow cooling (2 °C/h).
Journal ArticleDOI
Exploration of terahertz from time-resolved ultrafast spectroscopy in single-crystal Bi2Se3 topological insulator
TL;DR: In this article, the authors reconnoiter the differential reflection signal of a Bi2Se3 single-crystal flake, using ultrafast transient absorption spectroscopy in the femtosecond time domain and explore the experimental data in terms of terahertz frequency generated in the sample.
Journal ArticleDOI
Ionic-liquid-gating induced protonation and superconductivity in FeSe, FeSe0.93S0.07, ZrNCl, 1T-TaS2, and Bi2Se3
Yi Cui,Ze Hu,Jianbo Zhang,W. L. Ma,Mingwei Ma,Zhen Ma,Cong Wang,Jiaqiang Yan,Jianping Sun,Jinguang Cheng,Shuang Jia,Yuan Li,Jinsheng Wen,Hechang Lei,Pu Yu,Wei Ji,Weiqiang Yu +16 more
TL;DR: In this article, an ionic-liquid-gating method, with optimized gating conditions, was used to obtain single superconducting phases for several compounds, including ZrNCl, BiSe, and FeSe.
Journal ArticleDOI
Modeling of magneto-conductivity of bismuth selenide: a topological insulator
Yogesh Kumar,Yogesh Kumar,Rabia Sultana,Prince Sharma,Prince Sharma,V. P. S. Awana,V. P. S. Awana +6 more
TL;DR: In this paper, the authors reported the magneto-conductivity analysis of Bi2Se3 single crystal at different temperatures in a magnetic field range of 14 T to 5 K and a temperature of 5 K.
Journal ArticleDOI
Low-temperature ultrafast optical probing of topological bismuth selenide
Prince Sharma,Prince Sharma,Rahul Sharma,V. P. S. Awana,V. P. S. Awana,Tharangattu N. Narayanan,Bipin Kumar Gupta,Bipin Kumar Gupta,Nikita Vashistha,Nikita Vashistha,Lavi Tyagi,Mahesh Kumar,Mahesh Kumar +12 more
TL;DR: In this paper, the optical response and temperature-dependent excited-state carrier dynamics in the flake of Bi2Se3, which is cleaved from its single crystal, were explored using the VIS-NIR, IR, and photoluminescence (PL) spectroscopies.
References
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