Structural role of the pressure-dependent charge-density-wave to superconductor transition in $ZrTe_{3}$: an inelastic light scattering study

One of the most exciting areas of condensed matter research involves the study of how superconductivity evolves from magnetic- or charge-ordered phases in strongly correlated systems. We present a Raman scattering study of the temperature- and pressure-induced structural changes leading to the transition between charge-density wave (CDW) and superconducting phase regimes in $ZrTe_{3}$. We show that the internal deformation modes associated with the Te-Te chains--which support the CDW in this material--exhibit anomalous linewidth changes as a function of temperature, indicating strong electron-phonon coupling associated with these modes. Additionally, the pressure-dependence of these modes suggests that dissociation of the Te-Te chain bonds may be responsible for the suppression of the CDW phase as a function of pressure. These studies provide insight into the structural changes responsible for CDW collapse in this material.