相关论文: Pressure induced electronic topological transition…
The nontrivial electronic topology of a topological insulator is thus far known to display signatures in a robust metallic state at the surface. Here, we establish vibrational anomalies in Raman spectra of the bulk that signify changes in…
In recent years, a low pressure transition around P $\sim$ 3 GPa exhibited by the A$_2$B$_3$-type 3D topological insulators is attributed to an electronic topological transition (ETT) for which there is no direct evidence either from theory…
We report Raman signatures of electronic topological transition (ETT) at 3.6 GPa and rhombohedral ({\alpha}-Bi2Te3) to monoclinic ({\beta}-Bi2Te3) structural transition at ~ 8 GPa. At the onset of ETT, a new Raman mode appears near 107 cm-1…
We report high pressure Raman experiments of Black phosphorus up to 24 GPa. The line widths of first order Raman modes A$^1_g$, B$_{2g}$ and A$^2_g$ of the orthorhombic phase show a minimum at 1.1 GPa. Our first-principles density…
Raman spectra of the MgB2 ceramic samples were measured as a function of pressure up to 32 GPa at room temperature. The spectrum at normal conditions contains a very broad peak at ~590 cm-1 related to the E2g phonon mode. The frequency of…
We report a theoretical \textit{ab-initio} study of $\beta$-As$_2$Te$_3$ ($R\bar{3}m$ symmetry) at hydrostatic pressures up to 12 GPa. We have systematically characterized the vibrational and electronic changes of the system induced by the…
We performed X-ray diffraction and electrical resistivity measurement up to pressures of 5 GPa and the first-principles calculations utilizing experimental structural parameters to investigate the pressure-induced topological phase…
Topological superconductivity with Majorana bound states, which are critical to implement nonabelian quantum computation, may be realized in three-dimensional semimetals with nontrivial topological feature, when superconducting transition…
We report measurements of the superconducting critical temperature Tc of polycrystalline MgB2 samples containing isotopically pure (10)B and (11)B under quasi-hydrostatic pressure conditions in He pressure media up to 44 GPa. Measurements…
The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase…
We investigate the nonequilibrium photocarrier dynamics of WTe2 under pressure using the optical pump-probe spectroscopy. The pressure dependences of the electronic relaxation manifest anomalous changes around 0.8, 3.5, and 6 GPa,…
High pressure Raman spectroscopy of bulk 2H-MoTe$_2$ upto $\sim$ 29 GPa is shown to reveal two phase transitions (at $\sim$ 6 and 16.5 GPa), which are analyzed using first-principles density functional theoretical calculations. The…
Two pressure-induced phase transitions have been theoretically studied in the layered iron phosphorus triselenide (FePSe3). Topological analysis of chemical bonding in FePSe3 has been performed based on the results of first-principles…
Since there is both strong electron-phonon coupling during a ferroelectric/FE transition and superconducting/SC transition, it has been an important topic to explore superconductivity from the FE instability. Sn$_2$P$_2$Se$_6$ arouses broad…
Recently discovered class of 2D materials based on transition metal phosphorous trichalcogenides exhibit antiferromagnetic ground state, with potential applications in spintronics. Amongst them, FePS$ _{3} $ is a Mott insulator with a band…
One approach to discovering topological superconductor is establishing superconductivity based on well-identified topological insulators. However, the coexistence of superconductivity and topological state is always arcane. In this paper,…
ZrSiS has recently gained attention due to its unusual electronic properties: nearly perfect electron-hole compensation, large, anisotropic magneto-resistance, multiple Dirac nodes near the Fermi level, and an extremely large range of…
Here we present the superconducting property and structural stability of kagome CsV3Sb5 under in-situ high pressures. For the initial SC-I phase, its Tc is quickly enhanced from 3.5 K to 7.6 K and then totally suppressed at P~10 GPa.…
We report high-pressure photoluminescence, Raman scattering, and x-ray diffraction measurements on a lead-free halide perovskite $Cs_3Sb_2Br_9$. At about 3 GPa, an electronic transition manifests itself through a broad minimum in linewidth,…
Recent progress in understanding the electronic band topology and emergent topological properties encourage us to reconsider the band structure of well-known materials including elemental substances. Controlling such a band topology by…