Physicists reveal a strange form of crystal where electrons cannot move: ScienceAlert

Quantum traffic laws applied to the 3D streets of a certain type of crystal could put the brakes on electronic rush hour.

In the search for new materials that could contain new and exotic states of matter, physicists from Rice University in the US led an experiment that forced free electrons to stay in place.

While this phenomenon has been seen in materials in which electrons are bound Only two moreThis is the first time it has been observed in a three-dimensional crystalline mineral lattice, known as pyrochlore. This technique gives researchers a new tool to study the less conventional activities of charge-carrying particles.

“We are looking for materials that potentially have new states of matter or new exotic features that have not yet been discovered.” He says Rice University physicist Ming Yi.

Just as light can be described in ways similar to waves and particles, so too can the building blocks of atoms.

The quantum wave behavior of electrons is essential for understanding how their activity is coordinated under certain conditions. After being cooled, the electron waves can combine with each other in acts of entanglement that allow them to glide through solid materials like ghosts, giving rise to energy-efficient materials called superconductors.

Electron behavior can be managed in other ways. Arranging the right proportions of elements together creates unique intersections that look a bit like traffic lights, reducing what could be a chaotic bustle of pedestrians and commuters into a gentle crawl in what is described as Engineering frustration.

Perchlorate They are complex minerals with a specific structure that makes them useful for a range of research and industrial purposes. Constructing one from a mixture of copper, vanadium, and sulfur gave researchers an engineered foil metal that can direct electron waves to choke points.

“This quantum interference effect is like waves rippling across the surface of a pond and meeting head-on.” He says Yes.

“The collision creates a stationary wave that does not move. In the case of geometrically frustrated lattice materials, it is the electronic wave functions that interfere destructively.”

A technique called Specific angle photoemission spectroscopy It allowed the team to measure the energy and momentum of electrons in the 3D lattice, showing that one is not as dependent on the other as usual.

In this extraordinary space known as A Flat bandInteractions between passive electrons are governed by a different set of rules that could – in theory – give physicists a new way to understand electromagnetic phenomena such as superconductivity.

While similar localized electrons have been seen in 2D materials known as Kagome lattices, the appearance of a flat band of interfering waves making their way through a 3D lattice provides proof of concept that could lead to an entirely new class of materials.

“Pyrochlor isn’t the only game in town.” He says Rice University physicist Kimiao Si.

“This is a new design principle that allows theorists to predictively identify materials in which flat bands arise due to strong electronic correlations.”

This research was published in Nature physics.