Understanding the charge density wave phase transition in 1T-TiSe₂

The presence of competing order parameters between Charge Density Waves (CDW) and the superconducting phase adds interest to studying this behavior. CDWs can be effectively influenced by various factors such as electronic perturbations, strain, or ion intercalation. Transition Metal Dichalcogenides (TMDCs) represent a promising class of compounds for investigating such correlated orders. This study has specifically concentrated on the impact of intercalation on CDW ordering. We have explored the influence of intercalation on the transition temperature of CDW, T_CDW, in TiSe₂. Our findings indicate that less intercalated TiSe₂ exhibits a transition temperature of around 165 K, which decreases to 120 K following intercalation. Additionally, the observed dip in the local density of states could be directly connected to the redshift and change in the phonon lineshape observed in the 94.5 cm⁻¹ mode of the Raman measurement. This directly signifies the role of electron-phonon coupling in the charge density wave (CDW) phase transition. This advancement enhances the understanding of CDW phases, leading the way for next-generation quantum technologies.