US Nuclear Weapons Lab Discovers How To Suppress the Casimir Force

KentuckyFC writes "One of the frustrating problems with microelectromechanical (MEM) devices is that the machinery can sometimes stick fast, causing them to stop working. One of the culprits is the Casimir effect — an exotic force that pushes metallic sheets together when they are separated by tiny distances. Now physicists at the Los Alamos National Laboratory in New Mexico have worked out and demonstrated how to suppress the Casimir force. The trick is to create a set of deep grooves and ridges in the surface of one sheet so that the other only comes close to the tips of the ridges. These tips have a much smaller surface area than the flat sheet and so generate much less force. That could help prevent stiction in future MEMs devices. But why would a nuclear weapons lab be interested? MEM devices are invulnerable to electromagnetic pulse weapons that fry transistor-based switches, and so could be used as on-off switches for nuclear devices."

Thermionic valves also work

[jd]

Totally immune to EMP. Besides, we need people to magnify the Casimir effect if we're to ever get wormhole technology. And, trust me on this, you do NOT want an evil general on the other side to go around suppressing it when you're half-way through.

Re:Invulnerable? Really?

[wagnerrp]

An isolated MEMS is immune to electromagnetic pulses as the atmospheric saturation voltage is too low to produce sufficient potential in a system that small to damage it. If the MEMS is electrically connected to larger external systems, the potential across the contact points could be sufficient to cause damage.

Re:Prior Technology

[Anonymous Coward]

Not sure if I agree. I think the research is interesting. (Also, the Casimir force is _not_ like friction: it appears in conductive materials only.)

1. They've managed to make the super-tiny grooves needed at an unheard of precision. Sub-100 nm features have little in common with grooved surfaces.
2. The grating they've developed confirms the prediction that Casimir force is proportional to area.
3. The grating has effects going beyond existing theory:

Replacing a flat surface with a deep metallic lamellar grating with sub-100 nm features strongly suppresses the Casimir force and for large inter-surfaces separations reduces it beyond what would be expected by any existing theoretical prediction. (Abstract)

Re:Obvious/Common sense wins again

[Anonymous Coward]

Make the force repulsive? Um, no. The force arises as the difference between the sum of energies of different wavelengths outside the gap versus those inside the gap.

Unless you can figure out a way to make the gap bigger on the inside than on the outside, which would be cool and lead to technologies like a bag-of-holding, if not a full-fledged TARDIS, you're out of luck.

Sure, physicists can speculate on which combination of geometries might make a TARDIS possible, but nobody has been able to say for sure how this might be done.