Investigation of the charge order and the crystal structure in uniaxially pressurized YBa2Cu3O6+x

Superconducting cuprates universally have a propensity towards charge ordering. Superconductivity and charge order (CO) show an intricate competition that can be tuned by external parameters such as magnetic field, hydrostatic and uniaxial pressure. Experiments under uniaxial compression have revealed that a dramatic nonlinear suppression of the superconducting Tc favors a long-ranged 3D CO. For now, large pressures have been applied to YBa2Cu3O6.67 (Tc=65 K), a doping at which CO is strongest in the absence of pressure. However, the doping dependence at high pressure remains to be investigated. During our recent x-ray diffraction (XRD) experiment on YBCO6.67 under uniaxial compression, we have followed the evolution of 2D CO and the emergence of the 3D CO state while simultaneously monitoring the modifications of the lattice. Here we propose to extend our study to different dopings and to investigate the CO in uniaxially strained YBa2Cu3O6.55 (Tc=60K) and YBa2Cu3O6.80 (Tc=82 K).