2025/12/20 by Avishek Maity, Stephan Rosenkranz, Maity, Avishek +19
Materials Science · Physics and Astronomy · #Advanced Thermoelectric Materials and Devices #FOS: Physical sciences #Organic and Molecular Conductors Research #Strongly Correlated Electrons (cond-mat.str-el) #Topological Materials and Phenomena
paper · doi:10.48550/arxiv.2512.18472
openalex publication_date 2025/12/20 · openalex created_date 2025/12/24 · openalex updated_date 2026/07/28
We investigated the lattice dynamics of quasi-two-dimensional Pd-intercalated ErTe3 in relation to its charge-density-wave (CDW) transitions by means of x-ray diffuse and meV-resolution inelastic x-ray scattering. In pristine ErTe3, CDW order develops at orthogonal in-plane wave vectors \boldsymbolq1c = (0, 0, 0.29) (the c-CDW) and \boldsymbolq2a = (0.31, 0, 0) (the a-CDW), with transition temperatures T1c = 270 K and T2a = 160 K, respectively. Remarkably, we observe diffuse x-ray scattering already near the higher transition temperature T1c along a-CDW but at a slightly different wave vector \boldsymbolq1a = (0.29, 0, 0). Inelastic x-ray scattering for Pd0.01ErTe3 shows that a partial phonon softening at \boldsymbolq1a, underscoring the strong competition between ordering tendencies along the nearly equivalent in-plane axes of the orthorhombic lattice. For intercalation levels x ≥ 0.02, the a-CDW state is suppressed. Nevertheless, a similar correlation between phonon softening and diffuse scattering persists along the [100] direction, again observed at \boldsymbolq1a = (0.29, 0, 0) and T1c. These findings suggest that the a-CDW is fully suppressed for x ≥ 0.02, and that the residual diffuse scattering at \boldsymbolq1a originates from the partial phonon softening associated with the c-CDW, reflected by the near equality of the absolute size of \boldsymbolq1c and \boldsymbolq1a.