Electrical voltage can flip a universal law of attraction into a repulsive force that pushes nanostructures apart.
Van der Waals forces are the fundamental sticky interactions that usually make all small objects attract each other. By applying a specific bias voltage, researchers have found a way to make these interactions repulsive. This turns a constant of nature into a tunable switch that can be controlled with a battery. It provides a new way to prevent tiny machine parts from sticking together and wearing out. This discovery could lead to nearly frictionless nanomachines and new types of sensors.
Voltage-Tunable Nonequilibrium Dispersion Interactions
arXiv · 2605.02315
We develop a nonequilibrium Green's function theory for dispersion interactions between two nanostructures, each an open quantum system driven into a nonequilibrium steady state by an applied bias voltage. Starting from the two-particle nonequilibrium Green's function, we derive a general expression for the interaction energy in terms of the polarisation propagators of the individual systems. The interaction energy admits a physically transparent decomposition into charge noise and charge dissip