Dependence of Tc of YBa2Cu3O6.67 on in-plane uniaxial stress

Abstract

We probe the effect on ${T}_{\text{c}}$ of in-plane uniaxial stress applied to the high-temperature superconductor ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.67}$. We find a highly anisotropic response. Under compression along the $b$ axis, which reduces the orthorhombicity of the ${\mathrm{CuO}}_{2}$ planes, ${T}_{\text{c}}$ is broadly flat for stresses up to at least 1.7 GPa. Under compression along the $a$ axis, ${T}_{\text{c}}$ decreases steeply. For stresses beyond $\ensuremath{\approx}1$ GPa the decrease is quasilinear. We hypothesize that superconductivity is suppressed by competition with uniaxial charge density wave order, which has been found to onset at $\ensuremath{\approx}1$ GPa.