At ambient pressure, the LBCO-0.125 crystal barely conducts electricity without loss. Inside, electrons arrange into stripes with alternating magnetization, and these stripes act as barriers: superconducting pairs form but cannot flow freely through the whole sample. The superconducting transition temperature is only 5 K, just above the boiling point of liquid helium.
Researchers squeezed the crystal along one axis with a force of 0.5 GPa (equivalent to the pressure at a depth of 50 km underground). The magnetic stripes did not vanish, but their volume fraction dropped by about half. At the same time, the electrical resistance peak associated with lattice distortion disappeared. As a result, superconductivity blossomed: zero resistance appeared at 37 K, with the first signs of the transition at 46 K. That is above the boiling point of neon.
The reason why compression at exactly 45 degrees to the copper-oxygen bonds produced this effect is not yet clear. Perhaps it selectively disrupts the stripe order without affecting beneficial interactions. This opens a path to superconductors that work at higher temperatures.
A pressure of 0.5 GPa is equivalent to the weight of five cars resting on a thumbnail.
In Larry Niven's novel Ringworld, superconductors are used to contain plasma and for levitation, but there they work at room temperature, something the heroes of this article can only dream of.