We propose and analyze a scheme for parametrically cooling bilayer cuprates based on the selective driving of a $c$-axis vibrational mode. The scheme exploits the vibration as a transducer making the Josephson plasma frequencies time-dependent. We show how modulation at the difference frequency between the intra- and interbilayer plasmon substantially suppresses interbilayer phase fluctuations, responsible for switching $c$-axis transport from a superconducting to resistive state. Our calculations indicate that this may provide a viable mechanism for stabilizing non-equilibrium superconductivity even above $T_c$, provided a finite pair density survives between the bilayers out of equilibrium.
Denny, S. J., Clark, S. R., Laplace, Y., Cavalleri, A., & Jaksch, D. (2015). Proposed parametric cooling of bilayer cuprate superconductors by terahertz excitation. Physical Review Letters, 114(13), 1-5. . https://doi.org/10.1103/PhysRevLett.114.137001