Surface electronic structure and charge modulations in Pt-doped topological material NbIrTe₄

Ternary transition metal chalcogenides appear to host an array of interesting properties including topological states, superconductivity, and quantum spin Hall effect[1-3]. NbIrTe₄ features an orthorhombic lattice structure with broken inversion symmetry, and exhibits pressure-induced superconductivity, nonsaturating magnetoresistance, and a nonlinear Hall effect persisting above room temperature [4-6].

Here we present recent scanning tunneling microscope (STM) studies indicating the impact of Platinum(Pt) substitution on the electronic structure of bulk NbIrTe₄ at low temperature. Periodic charge modulations at angle of ±15 degrees to the lattice were observed consistent with the emergence of a charge density wave (CDW) phase, which was not observed on intrinsic samples. Quasiparticle interference on both Pt-substituted and stoichiometric samples provides insight into underlying electronic instabilities which may give rise to low temperature phases underpinning distortions and potentially superconductivity.

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