Change in the electronic structure of the bismuth chalcogenide superconductor CsBi_4−x Pb _x Te₆ by dissociation of the bismuth dimers

Abstract

CsBi 4−x Pb x Te 6 is synthesized and the superconductivity associated with the structural transition from Pb substitution is studied. Photoemission spectroscopy measurements are performed in order to elucidate the relationship between the electronic structure and the occurrence of the superconductivity. When Bi is substituted with Pb, an electron dopinglike change in the electronic structure is directly observed which is contrary to the naive expectation of hole doping. This observation is consistent with band structure calculations and appears to be a unique characteristic of CsBi 4−x Pb x Te 6 because of the dissociation of Bi dimers upon Pb substitution. These results indicate that it may be possible to control the electron and hole doping via manipulating the Bi dimers through Pb substitution.

The non-centrosymmetric layered compounds IrTe2I and RhTe2I

“…Inorganic heavy metal compounds based on halogens and/or chalcogens have been studied for decades due to their electronic and magnetic properties and multiple potential applications. This family includes thermoelectric materials, [1][2][3] applications in photovoltaic devices 4,5 and radiation detectors, 6,7 and quantum materials [8][9][10][11] for example. Especially of recent interest have been heavy transition metal chalcogenides or halides with layered crystal structures, as their resulting pseudo 2D electronic and magnetic systems, together with the van der Waals forces between the layers, provide both a platform for studying forefront spin/electron interactions, and for further fabrication and modification.…”