Quantum tornadoes generated on semiconductors

December 05, 2012 // By Sylvie Barak
Ever heard of a tempest in a teacup? Sure. But what about a tornado on a chip? According to some rather bizarre research being undertaken by a group of scientists at the University of Cambridge in the U.K., quantum fluid trapped on top of a semiconductor chip, which manifests itself as a sort of tornado-like vortex, can be used to measure movements.

Apparently, a mass of these quantum twisters can line up like a regiment of tiny soldiers, allowing for the engineering of quantum circuits and chips that will allow super precise motion measurement.

If that sounds confusing, it’s because it is. We’re talking quantum physics here, that branch of science that requires quantum leaps of imagination.

Polariton quantum rivers flow from four hills creating quantum tornadoes in the valley.
Credit: Natasha Berloff from DAMTP

The Cambridge scientists, however, have explained it by saying the tiny twisters generated on the surface of a semiconductor chip can be controlled, something most big twisters of the Wizard of Oz variety cannot be.

By controlling where electrons move and how they interact with light, the scientists managed to merge electrons and photons into a new quantum particle they call "polariton."

These polaritons are half-light and half matter, making them “feather-light” and rather zippy, with researchers describing their movements similar to cascading water in a mountain river. The quantum systems are also actually rather big, on a microscopic scale, spanning the width of a human hair, making them easy to observe.

The team, led by Professor Jeremy Baumberg and the theoretical quantum fluids group of Dr Natalia Berloff, has been able to do all kinds of unexpected things with the “liquid” on chips’ surface, forcing it to flow in various directions, over bumps and letting it “settle” into “wildly raging quantum oceans.”

The long and short of the matter is that playing with mini quantum tornadoes on a chip is actually allowing scientists to both create and control macroscopic quantum states.

What’s that good for? Well, research and science, of course. So much so, in fact, that the study has been granted funding from the Engineering and Physical Sciences Research Council and the European Union.

That being said, a tempest in a teacup now makes a lot more sense to me than quantum physics ever could.