Charge density wave incommensuration in tise2 systems measured with hard x-ray scattering

Abstract

Unconventional superconductivity cannot be understood independently of the phases that order around it. Characterizing the charge order in modulated superconductors provides essential information that could reveal a common underlying mechanism. We performed low temperature experiments on 1T-TiSe 2 crystals tuned by three parameters: pressure, copper intercalation, and sulfur substitution. Resistivity measurements revealed a previously unreported superconductive phase in sulfur substituted samples. Our hard x-ray diffraction experiments determined that the charge order phase does not terminate inside the superconductive phase of these systems, as was formerly believed. The phase diagrams established in this work suggest that incommensurations of the charge density wave could play a role in the emergence of superconductivity.