Phase Diagram for Light-Induced Superconductivity in κ-(ET)2-X

Resonant optical excitation of certain molecular vibrations in kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br has been shown to induce transient superconductinglike optical properties at temperatures far above equilibrium T-c. Here, we report experiments across the bandwidth-tuned phase diagram of this class of materials, and study the Mott insulator kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Cl and the metallic compound kappa-(BEDT-TTF)(2)Cu(NCS)(2). We find nonequilibrium photoinduced superconductivity only in kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br, indicating that the proximity to the Mott insulating phase and possibly the presence of preexisting super-conducting fluctuations are prerequisites for this effect.

Automated summary

The resonant optical excitation of certain molecular vibrations in kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br has been shown to induce transient superconducting-like optical properties at temperatures far above equilibrium T-c. The study across the bandwidth-tuned phase diagram suggests that proximity to the Mott insulating phase and possibly the presence of preexisting superconducting fluctuations are prerequisites for this effect, as only kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br exhibits nonequilibrium photoinduced superconductivity.