Creating the "Rarest Material on the Planet" - Metallic Hydrogen

Harvard University researchers have created metallic hydrogen, nearly a century after it was first theorized. In addition to helping scientists answer fundamental questions about the nature of matter, the material could have a wide range of applications, from room-temperature superconductors to powerful rocket propellant. A room temperature superconductor could change the transportation system, enabling magnetic levitation of high-speed trains. In their experiments, the researchers squeezed a tiny hydrogen sample at 495 gigapascal (GPa), or more than 71.7 million pounds per square inch - greater than the pressure at the center of the Earth. At such extreme pressures, solid molecular hydrogen, which consists of molecules on the lattice sites of the solid, breaks down, and the tightly bound molecules dissociate to transform into atomic hydrogen, a metal.

Transcript

00:00:08 We have made a new material it's a material that has never existed on earth before: metallic hydrogen. Hydrogen is the simplest atom in the periodic table of the elements, it consists of a single proton with the single electron around it, at room temperature, it exists as a gas but if you cool hydrogen down to low temperatures it actually

00:00:34 liquefies and if I cool it to about just under 14 degrees it forms a solid. Imagine my fingers are molecules here with the two atoms, if you compress it to a high enough density eventually you will get to a pressure or a density where the molecules dissociate and it forms an atomic solid and this is a metal. You have two diamonds sitting opposite to each other inside here we load the sample as a

00:01:08 liquid state, but as soon as you pressurize it, the molecules get closer together it becomes a solid, and then we're squeezing the solid, and even though this device looks very small we can generate pressure more than the center of earth. You never know how it's going to be applied but imagine that it's metastable and you can make electrical wires out of it, you could conduct electricity across

00:01:32 the country without dissipation, you could make magnets which are used in MRI, for example, that would work at room temperature. Right now the magnets have to be cooled with liquid helium. NASA has supported some of our research because it turns out that if it's metastable and you could cause it to convert to molecular hydrogen, it releases an enormous amount of energy and it would

00:01:55 revolutionize rocketry and it's a very nice thing to achieve.