1 research outputs found
Recommended from our members
Dimensional Effects on the Charge Density Waves in Ultrathin Films of TiSe<sub>2</sub>
Charge
density wave (CDW) formation in solids is a critical phenomenon
involving the collective reorganization of the electrons and atoms
in the system into a wave structure, and it is expected to be sensitive
to the geometric constraint of the system at the nanoscale. Here,
we study the CDW transition in TiSe<sub>2</sub>, a quasi-two-dimensional
layered material, to determine the effects of quantum confinement
and changing dimensions in films ranging from a single layer to multilayers.
Of key interest is the characteristic length scale for the transformation
from a two-dimensional case to the three-dimensional limit. Angle-resolved
photoemission spectroscopy (ARPES) measurements of films with thicknesses
up to six layers reveal substantial
variations in the energy structure of discrete quantum well states;
however, the temperature-dependent band gap renormalization converges
at just three layers. The results indicate a layer-dependent mixture
of two transition temperatures and a very-short-range CDW interaction
within a three-dimensional framework