Pressure induced superconducting state in ideal topological insulator BiSbTe₃

Abstract

Structural, pressure-dependent resistivity, angle resolved photoemission spectroscopy (ARPES), x-ray photoelectron diffraction (XPD) and band structure by DFT calculation have been investigated for BiSbTe3 Topological insulator. It has been demonstrated that the Dirac point of the topological surface state (TSS) located 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). It has also been shown that the surface state remains unchanged under pressure and has been suggested that the origin of the superconductivity is due to the bulk state. The investigation indicates that the BiSbTe3 has robust surface states and becomes superconductor under pressure.

Anharmonic phonon interactions and the Kondo effect in a FeSe/Sb2Te3/FeSe heterostructure: a proximity effect between ferromagnetic chalcogenide and di-chalcogenide

“…12–14 The resistivity varies linearly with temperature between 20 and 60 K. Below 15 K, resistance displays a specific feature corresponding to the Kondo effect (Fig. 3(b)), where the R – T data of the heterostructure was fitted using an abridged Kondo model given by; 15–17 where R o signifies the residual resistance occurring due to atomic disorder in the system. The T 2 and T 5 terms imply the electron–electron and electron–phonon interactions, respectively.…”

“…The T 2 and T 5 terms imply the electron–electron and electron–phonon interactions, respectively. The characterizing parameters were estimated using the following equation; 15–17 where T ′ k = T k /(2 1/S − 1) 1/2 and S was secured to 0.225. All the evaluated parameters from the Kondo model fitting shown in Fig.…”

“…[12][13][14] The resistivity varies linearly with temperature between 20 and 60 K. Below 15 K, resistance displays a specific feature corresponding to the Kondo effect (Fig. 3(b)), where the R-T data of the heterostructure was fitted using an abridged Kondo model given by; [15][16][17]…”

“…The T 2 and T 5 terms imply the electron-electron and electron-phonon interactions, respectively. The characterizing parameters were estimated using the following equation; [15][16][17]…”

“…These transverse resistivity data show a positive slope with H, which strongly recommends that the p-type charge carriers are dominating in our system. 17,19 The estimated values of carrier concentration (n e ) and carrier mobility (μ e ) from Hall resistivity data at different temperatures are presented in the top corner insets of Fig. 3(c).…”