Pressure-induced superconductivity in the Zintl topological insulator SrIn2As2
Physical Review B American Physical Society (APS) 108:22 (2023) 224510
Correction to: Measurement of the electronic structure of a type-II topological Dirac semimetal candidate VAl3 using angle-resolved photoelectron spectroscopy
Tungsten Springer Nature 5:4 (2023) 608-608
Pressure-Induced Superconductivity and Topological Quantum Phase Transitions in the Topological Semimetal ZrTe2.
Advanced science (Weinheim, Baden-Wurttemberg, Germany) 10:35 (2023) e2301332
Abstract:
Topological transition metal dichalcogenides (TMDCs) have attracted much attention due to their potential applications in spintronics and quantum computations. In this work, the structural and electronic properties of topological TMDCs candidate ZrTe2 are systematically investigated under high pressure. A pressure-induced Lifshitz transition is evidenced by the change of charge carrier type as well as the Fermi surface. Superconductivity is observed at around 8.3 GPa without structural phase transition. A typical dome-shape phase diagram is obtained with the maximum Tc of 5.6 K for ZrTe2 . Furthermore, the theoretical calculations suggest the presence of multiple pressure-induced topological quantum phase transitions, which coexists with emergence of superconductivity. The results demonstrate that ZrTe2 with nontrivial topology of electronic states displays new ground states upon compression.Topological electronic structure and spin texture of quasi-one-dimensional higher-order topological insulator Bi4Br4.
Nature communications 14:1 (2023) 8089
Abstract:
The notion of topological insulators (TIs), characterized by an insulating bulk and conducting topological surface states, can be extended to higher-order topological insulators (HOTIs) hosting gapless modes localized at the boundaries of two or more dimensions lower than the insulating bulk. In this work, by performing high-resolution angle-resolved photoemission spectroscopy (ARPES) measurements with submicron spatial and spin resolution, we systematically investigate the electronic structure and spin texture of quasi-one-dimensional (1D) HOTI candidate Bi4Br4. In contrast to the bulk-state-dominant spectra on the (001) surface, we observe gapped surface states on the (100) surface, whose dispersion and spin-polarization agree well with our ab-initio calculations. Moreover, we reveal in-gap states connecting the surface valence and conduction bands, which is a signature of the hinge states inside the (100) surface gap. Our findings provide compelling evidence for the HOTI phase of Bi4Br4. The identification of the higher-order topological phase promises applications based on 1D spin-momentum locked current in electronic and spintronic devices.Anomalous excitonic phase diagram in band-gap-tuned Ta2Ni(Se,S)5.
Nature communications 14:1 (2023) 7512