> Their work, now published in Nature Communications, also shows that the electrical response of photo-excited K3C60 is not linear, that is, the resistance of t

> Their work, now published in Nature Communications, also shows that the electrical response of photo-excited K3C60 is not linear, that is, the resistance of the sample depends on the applied current. This is a key feature of superconductivity, validates some of the previous observations and provides new information and perspectives on the physics of K3C60 thin films. "Superconducting nonlinear transport in optically driven high-temperature K3C60" (2023) https://www.nature.com/articles/s41467-023-42989-7 https://www.nature.com/articles/s41467-023-42989-7 : > Abstract: Optically driven quantum materials exhibit a variety of non-equilibrium functional phenomena, which to date have been primarily studied with ultrafast optical, X-Ray and photo-emission spectroscopy. However, little has been done to characterize their transient electrical responses, which are directly associated with the functionality of these materials. Especially interesting are linear and nonlinear current-voltage characteristics at frequencies below 1 THz, which are not easily measured at picosecond temporal resolution. Here, we report on ultrafast transport measurements in photo-excited K3C60. Thin films of this compound were connected to photo-conductive switches with co-planar waveguides. We observe characteristic nonlinear current-voltage responses, which in these films point to photo-induced granular superconductivity. Although these dynamics are not necessarily identical to those reported for the powder samples studied so far, they provide valuable new information on the nature of the light-induced superconducting-like state above equilibrium Tc. Furthermore, integration of non-equilibrium superconductivity into optoelectronic platforms may lead to integration in high-speed devices based on this effect.