By controlling where electrons move and how they interact with light, a research team from Cambridge University has formed a new quantum particle called a polariton.
The collaboration involved an experimental team from the NanoPhotonics Centre led by Professor Jeremy Baumberg and one from the theoretical quantum fluids group of Dr Natalia Berloff. Dr Berloff said: "Being half light and half matter, these particles are feather light and move quickly around, sloshing and cascading much like water in a mountain river." The researchers add these quantum systems are large and their effects can be seen though a normal optical microscope. In fact, the team describes the polaritons as quantum tornadoes and believes they could be used to engineer quantum circuits. They use the analogy of a mountainous terrain; by creating polaritons at the top of several hills and letting them flow downhill, the group formed regular arrays of hundreds of tornadoes spiralling in alternating directions along well defined canyons. By changing the number of hills, the distance between them and the rate of polariton creation, the researchers could vary the separation, the size and number of the twister cores. The result, they say, is the ability to create and control macroscopic quantum states. Quantum tornadoes can, apparently, be reconfigured on the fly and may pave the way to widespread applications in the control of quantum fluid circuits.