A new phase of matter has been discovered hiding inside the crystal, after physicists dispersed the crystal with ultrasound laser light pulses.
The new phase of matter has appeared in a crystalline material called lanthanum tritelluride – made up of one lanthan atom and three tulurium atoms. Super short laser pulses were changing as the electrons moved through the crystal, and the change is enough to classify it as a completely new state of matter.
Energy loss usually makes substances less neat, like heat-melting ice or glass that breaks through sharp cracks, physicists say. But in this case, the laser flash seems to transmit the crystal in a rare degree to a higher degree.
"Normally, to change the material phase you are trying chemical changes, or pressure or magnetic fields. In this work, we use light to make these changes," said Massachusetts Technology Physician (MIT) Noah Gedick, one of the leaders at the experiment said in a statement.
Lanthanum triteluride crystals naturally form a layered structure, physicists say. And within that layered structure you will find an unusual pattern.
In most substances, the electrons are fairly evenly distributed. But at very low temperatures, lanthanum triteluride forms low electron density pockets and high electron density pockets. And these pockets are organized in a flat pattern pointing in the same direction as the crystal layers. Physicists call this scheme a wave of charge density.
But hit it in the crystal with laser light less than a trillionth of a second, and the charge density wave will sharply (and very briefly) change directions – flowing perpendicular to the direction it originally flowed. This is the new phase of matter that physicists have found.
In theory, the new phase of matter that appears after the laser flash exists as a kind of latent possibility in the crystal all the time. Laser light suppresses the dominant phase – that initial flow of electric charge – and allows the hidden phase to appear.
When the laser effect subsides, the original phase is reaffirmed. The researchers called the two phases "competitive states" in the crystal.
And there are probably other competing states out there, hiding in other crystalline substances, say researchers in a November 11 paper in the journal Nature Physics. And most likely they can be detected by laser light blinks. Over time, the researchers say, they could discover new ways to manipulate materials without flashing lights.
Originally posted on Live Science.