The record ambient-pressure superconducting transition temperature has been 133 K since 1993 — over three decades of stasis. Higher Tc values exist, but only under extreme pressures that prevent practical applications. The obvious question: can you stabilize a high-pressure superconducting state and then release the pressure?

This paper does exactly that. A pressure-quench protocol applied to the cuprate HgBa2Ca2Cu3O8+δ achieves a record ambient-pressure Tc of 151 K, breaking the thirty-year plateau. The material is compressed to stabilize an enhanced superconducting state, then the pressure is released rapidly enough that the structural changes persist. Synchrotron X-ray diffraction confirms the structural modifications survive at ambient pressure. Phonon and electronic structure calculations support the mechanism.

The breakthrough isn’t a new material — it’s a new processing route for an existing one. The superconducting state was always accessible in this compound under pressure. The pressure quench makes it permanent. This opens a strategy: survey the landscape of pressure-enhanced superconductors and ask which ones can be quenched. The record will likely move again.