First principles description of Charge Density Waves in single-layer TiSe₂ and TiTe₂.

We present some of our recent work on the understanding of the appearance of Charge Density Waves (CDW) in single-layer 2D transition metal dichalcogenides by means of first principles electronic structure calculations. This is done in connection with recent experimental studies that have been able to demonstrate the presence of CDS in several 2D single-layer materials like TiSe₂ and TiTe₂. The evolution of the CDW with external electrostatic doping, which has been achieved experimentally using field effect transistor setups, will be analyzed for the case of TiSe2 [1]. For TiTe2, we focus on the recently observed CDW in the single layer, which is not present in the bulk material [2].
[1] B. Guster, M. Pruneda, E. Canadell, P. Ordejón, 2D Mater. 5 (2018) 025024
[2] B. Guster, E. Canadell, R. Robles, M. Pruneda, P. Ordejón, submitted.