Fig. 1: Schematic equilibrium phase diagram hosting ephemeral superconductivity.
a As a function of tuning parameters (x, y) a superconducting region exists (SC, blue), surrounded by a parent “normal” state (PM, white) and a symmetry-broken correlated phase (red). The correlated phase suppresses an otherwise superconducting region in parameter space (hatched red-blue). Here, we consider a quench across a first-order transition boundary to the FV superconductor, either directly from an equilibrium superconducting phase (black arrow) or from the normal state (green arrow). b Illustration of the energy landscape as a function of the two order parameters ϕ, Ψ across the transition. In the equilibrium superconducting phase (left) Ψ is condensed (blue ellipse). Following the quench (black arrow), the new equilibrium state has ϕ condensation and zero superconductivity. The ephemeral superconductor (empty ellipse) has a finite lifetime of ~ τdecay before decaying to the true vacuum (via the dashed line trajectory).
