Collapse of high-T_c superconductivity via ultrafast quenching of the phase coherence

One of the most tantalizing properties of low-density condensates is the emergence of phase transitions driven solely by the fragility of the phase coherence. This intriguing physics has triggered an intense search for tools to control the rigidity of superconducting phases and investigate the collapse of superconductivity induced by phase fluctuations. Here, we exploit the capabilities of time-resolved photoemission spectroscopy to probe and drive the phase fragility of the Bi₂Sr₂CaCu₂O_8+δ cuprate superconductor, up to the point of completely quenching the phase coherence without affecting the electron pairing. In particular, we thoroughly track and disentangle the dynamics of phase fluctuations and charge excitations [1]. We demonstrate the dominant role of phase coherence in the emergence of high-temperature superconductivity. Moreover, we offer a new benchmark for non-equilibrium investigations of the phase diagram in the normal state at low electronic temperatures.

[1] Boschini et al., arXiv:1707.02305