Scientists Just Found an Unexpected Property in a Solid Metal: It 'Remembers' its Liquid State

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In this study, researchers from the Carnegie Institution for Science brought bismuth to a liquid state at pressures an incredible 14,000 to 24,000 times greater than normal atmospheric pressure, and about 1,250 Kelvin (977 degrees Celsius, or 1,800 degrees Fahrenheit).

When they slowly cooled that bismuth back down to a solid state, they found that the solid 'remembered' some of the structure of its liquid past life.

That doesn't mean the metal was morphing back into the same liquid shape it had before, but it was remembering the ferromagnetic properties of that liquid state and was being attracted to a magnetic field, rather than repelled by one.

"The high-pressure liquid becomes more structurally disordered when the heat is applied, taking on what we call a 'deep liquid' state, certain structural characteristics of which remain even when the bismuth is cooled back to solid," explained one of the researchers, Guoyin Shen.

"This is the first time such an effect has been seen in an elemental metal."

For now, it's very early days, and the team isn't entirely sure how this structural memory is stored in the metal, or how the solid bismuth is able to act as a ferromagnet, instead of being repelled by a magnet as it usually would.

"The physical origin of this surprising behaviour requires additional investigation," the team writes in the journal PNAS.

But they do think that this strange new property could also induce a similar shift in other elements, such as cerium, antimony, and plutonium. And if that's the case, it could lead to a whole new way of creating these elements with untapped properties.

The research has been  published in PNAS