In one minute

Tang, Wang, Ng, Nikolic, Chan, Rodriguez and Chan tackle a practical barrier: novel geometries that should give repulsive or non-monotonic Casimir forces are hard to align at close range. An on-chip platform with integrated force sensors and actuators removes the alignment problem and measures the force between two silicon surfaces with nanoscale protrusions. The Casimir force depends non-monotonically on displacement. At some displacements it confines the motion and effectively stiffens the nanomechanical spring. This opens the way to using the Casimir force in nanomachines built from unconventional shapes, and the same scheme can measure lateral Casimir forces between other novel structures.

Measurement of non-monotonic Casimir forces between silicon nanostructures