Engineering phase competition between stripe order and superconductivity in La1.88Sr0.12CuO4

Unconventional superconductivity often couples to other electronic orders in a cooperative or competing fashion. Identifying external stimuli that tune between these two limits is of fundamental interest. Here, we show that strain perpendicular to the copper-oxide planes couples directly to the competing interaction between charge stripe order and superconductivity in La1.88Sr0.12CuO4 (LSCO). Compressive c-axis pressure amplifies stripe order within the superconducting state, while having no impact on the normal state. By contrast, strain dramatically diminishes the magnetic field enhancement of stripe order in the superconducting state. These results suggest that c-axis strain acts as tuning parameter of the competing interaction between charge stripe order and superconductivity. This interpretation implies a uniaxial pressure-induced ground state in which the competition between charge order and superconductivity is reduced. Tuning superconductivity and its interplay with other phases in cuprates yields insights into the underlying physics of this material class. Here, the authors performed a hard x-ray diffraction experiment on La1.88Sr0.12CuO4 showing that uniaxial pressure along the c-axis acts as a direct tuning parameter of the competition between superconductivity and charge order.