Nature's Wonder ‑ Liquid Hydrogen

October 12, 2004

Nature's Wonder - Liquid Hydrogen

by Charles Crosby

The work of Dalhousie Physics and Atmospheric Science professor, Stanimir Bonev is featured on the cover of the latest issue of the British magazine, Nature, under the cover story: "Melting hydrogen: A new superfluid awaits."

An article by Dr. Stanimir Bonev, who recently joined the Department of Physics and Atmospheric Science, is featured on the cover of Nature.

Dr. Bonev's research provides strong theoretical evidence towards the existence of a brand new state of matter — a zero temperature liquid metal, that if found would be the first new superfluid (excluding the atomic vapors) in 32 years. Bonev is excited about the attention from Nature.

"When I started this project, I knew that it could be an important piece of work leading to a good publication," he says. "But the end result is beyond my best expectations. Things just kept getting better and better. I am very happy and also very satisfied because the success, of course, is partially due to luck, but it is also a pay-off for a long and hard work. I am glad that I can leave my, however small it is, mark in science. And I am also very happy that the spotlight coincides with my return to Halifax. It is a good way to come back."

Bone, a student at Dalhousie from 1992 to 1996, is a new addition to the Physics and Atmospheric Science department; he comes to Dalhousie from Lawrence Livermore National Laboratory at the University of California. His exciting research, begun at Lawrence Livermore will continue at Dal.

The findings of Bonev's research note that unusual phases of hydrogen are predicted to exist at high pressure. In particular, a metallic phase of solid hydrogen has been sought since the 1930s, but has so far proved elusive. Bonev and colleagues predict there may be more surprises on the way. They report first-principles calculations of the melting behaviour of solid molecular hydrogen. The results indicate that, before the metallic crystalline phase is attained, compressed hydrogen will first transform into a low-temperature quantum fluid at around 400 GPa (4 million atmospheres). Such a liquid would represent a new type of superfluid with exotic properties. The predicted properties of metallic hydrogen are discussed further in a separate report (also in the current issue of Nature) from Asle Sudbo, Egor Babaev and Neil Ashcroft.

They predict that, in the presence of a magnetic field, liquid metallic hydrogen might exhibit several states, ranging from superconductors to superfluids. In addition to this breakthrough research, Bonev is pleased at yet another positive outcome of the process: "Last but not least, we prepared a darn good picture for the cover of Nature."

The image is of a hydrogen molecule.