A. D. Caviglia et al. 
Illustration of the propagation of a vibrational mode from an LaAlO3 substrate (gray octahedra) into an epitaxially grown NdNiO3 nickelate layer (shown in green). Caviglia et al. used femtosecond infrared pulses to excite a stretching mode in the substrate, and measured transient conductivity of the nickelate by means of optical reflectivity. The results reveal a five orders of magnitude metastable increase in conductivity after the vibrational pulse alters the nickelate lattice and its electronic properties.