Physicists develop ‘supersolid’ that flows like a liquid, endlessly

3 Mar 2017

Image: Elena Larina/Shutterstock

MIT physicists’ latest trick is the creation of a supersolid, replicating the viscosity-free, endless flowing attributes of superfluids.

Imagine a liquid that enjoys absolutely no viscosity, flowing without the loss of any kinetic energy; essentially, a bowl of liquid, stirred around once and never needing to be stirred again, just rotating and rotating ad infinitum.

Now imagine that happening with a solid.

The former is, in essence, a superfluid. The latter is impossible. Or, was impossible.

MIT is reporting the development of a new form of matter, created by taking a superfluid gas known as a Bose-Einstein condensate, zapping it with lasers and turning it solid. The report has been published in Nature.

After the condensate was coaxed into a quantum phase of matter with a rigid structure, it essentially bridged into a supersolid.

Research into this bizarre form of matter could lend itself towards superconductors, and help physics to look beyond graphene for a silver bullet candidate.

According to MIT, studies in this field could help to improve technologies such as superconducting magnets and sensors, as well as efficient energy transport.

“It is counterintuitive to have a material which combines superfluidity and solidity,” said team leader Wolfgang Ketterle. “If your coffee was superfluid and you stirred it, it would continue to spin around forever.”

Ketterle received a Nobel Prize in physics for his work in discovering superfluids in 2001.

Hoping that helium could become a supersolid, a series of laser-led tests helped the team to cool atoms of sodium to nanokelvin temperatures. These bosons turned to a superfluid state of Bose-Einstein condensate when cooled to absolute zero.

To then turn it solid, more lasers helped to manipulate the motion of the atoms to such a degree that “density modulation” occurred.

Currently, the supersolid only exists at extremely low temperatures under ultra-high vacuum conditions.

“With our cold atoms, we are mapping out what is possible in nature,” explains Ketterle. “Now that we have experimentally proven that the theories predicting supersolids are correct, we hope to inspire further research, possibly with unanticipated results.”

Ketterle and his team might be on to something, as a second piece of research in the same issue of Nature, developed in Switzerland, showed another way to create supersolids.

Julian Leonard and a team of physicists used mirrors to help develop the new matter, again from Bose-Einstein condensate.

Gordon Hunt was a journalist with Silicon Republic