Quantum Plasmon Resonances Controlled by Molecular Tunnel Junctions

Controlling Quantum Plasmonics Electron tunneling across cavities could potentially induce a quantum mechanical plasmon mode that would be important in nano-electronics, catalysis, nonlinear optics, or single-molecule sensing, but has been expected to occur only at length scales beyond the reach of current state-of-the-art technology. Using a system of plasmonic dimers comprising silver nanocubes bridged by a molecular self-assembled monolayer, Tan et al. (p. 1496 ; see the Perspective by Nordlander ) observed quantum plasmonic tunneling between the resonators and were able to tune the frequency of this tunneling plasmon resonance via selection of the molecular tunnel junctions. Moreover, the effects were observed at length scales that are technologically accessible.