Nanostructure of a strain-induced charge-density wave in a 2D quantum material

In this experiment, we will study a strained-induced orientational transition of a charge-density-wave (CDW) that we recently evidenced in TbTe3, a nearly-tetragonal 2D van der Waals material. In the pristine state, the CDW is oriented along the in-plane c axis, and under tensile strain along the perpendicular in-plane direction a, the CDW disappears along c while it appears along a. We showed that this transition is directly related to the ratio of the in-plane lattice constants a/c, and takes place when a=c. However, the way the CDW along a appears still has to be elucidated. In particular, it could appear through the nucleation of domains. The aim of this experiment is to check this scenario using a nanobeam. If domains appear, we will study their evolution under strain. If not, we will validate a scenario of spatially-coexisting CDW. We will additionally get a spatially-resolved measurement of CDW q-vectors under strain, and study the role of temperature.