Charge density waves tuned by biaxial tensile stress
The precise arrangement and nature of atoms drive electronic phase transitions in condensed matter. To explore this tenuous link, we developed a true biaxial mechanical deformation device working at cryogenic temperatures, compatible with x-ray diffraction and transport measurements, well adapted to layered samples. Here we show that a slight deformation of TbTe3 can have a dramatic influence on its Charge Density Wave (CDW), with an orientational transition from c to a driven by the a/c parameter, a tiny coexistence region near a = c, and without space group change. The CDW transition temperature Tc displays a linear dependence |a / c – 1| with while the gap saturates out of the coexistence region. This behaviour is well accounted for within a tight-binding model. Our results question the relationship between gap and Tc in RTe3 systems. This method opens a new route towards the study of coexisting or competing electronic orders in condensed matter.
A. Gallo-Frantz, V.L.R. Jacques, A.A. Sinchenko, D. Ghoneim, L. Ortega, P. Godard, P.-O. Renault, A. Hadj-Azzem, J.E. Lorenzo, P. Monceau, D. Thiaudière, P.D. Grigoriev, E. Bellec, D. Le Bolloc’h