Manipulating stripes in La$_{2-x}$Ba$_{x}$CuO$_{4}$ in extreme environments

Competing magnetic and electronic interactions in the copper-oxide high temperature superconductors often result in nanoscale inhomogeneity of the charge and spin density. Such observations motivated a proposal that dynamic electronic inhomogeneities are intrinsic to the copper-oxide planes, and can result in electronic states that break their four-fold symmetry. We have performed high-energy single-crystal X-ray diffraction in high magnetic fields and at high pressure to show that the charge and spin stripe phase in La$_{2-x}$Ba$_{x}$CuO$_{4}$ constitutes such a state. In particular, our results provide strong evidence that charge stripe correlations in the cuprates are electronically driven and are enhanced within vortices.