In metals, electrons normally have diffusive movement, working somewhat like standalone particles, which means that they don’t achieve momentum as a group.
In a recent study, scientists discovered a type of metal where the electrons flow a lot like a fluid, similarly to how water flows in pipes by working with quasiparticles known as phonons, which appear from vibrations within crystal structures.
That led to the electrons to shift from particle-like behavior to hydrodinamic behavior (fluid-like) in their movement.
The discovery’s heart is a metal superconductor made out of niobium and germanium known as ditetrelide (NbGe2), according to the research team.
It has the potential of giving birth to a new generation of electronic devices.
Experimental physicist Fazel Tafti of the Boston College explained that the team tried to test a recent prediction of the “electron-phonon fluid.”
“Typically, electrons are scattered by phonons which leads to the usual diffusive motion of electrons in metals. A new theory shows that when electrons strongly interact with phonons, they will form a united electron-phonon liquid. This novel liquid will flow inside the metal exactly in the same way as water flows in a pipe,” he added.
Three experimental methods confirmed the electron-photon hypothesis speculated by Tafti and his colleagues.
The first consisted of measuring the electrical resistivity of the metal, which revealed that its electrons had a considerably greater mass than it would be normal.
Also, Raman scattering laser analysis revealed that the vibration of NbGe2 experienced modifications due to the unusual flow of electrons, and ultimately X-ray diffraction techniques uncovered the crystal structure of the metal.
The mass of electrons was roughly three times larger than it is normal, according to a material mapping approach called quantum oscillations, which is a solid sign that the metal’s electrons were behind the peculiar behavior.
Tafti said that the discovery surprised them because they weren’t expecting “heavy electrons” in an apparently simple metal.
“Eventually, we understood that the strong electron-phonon interaction was responsible for the heavy electron behavior. Because electrons interact with lattice vibrations, or phonons, strongly, they are ‘dragged’ by the lattice and it appears as if they have gained mass and become heavy,” he added.