This diagram models competing or ‘frustrated’ magnetic states in neighboring electrons. Condensed matter physicists use the term ‘frustrated’ to describe a kind of magnet in which the spins fail to align into a stable magnetic order. Their unique properties are of interest in the development of quantum computing and high-temperature superconductivity. Image: Ames Laboratory.
This diagram models competing or ‘frustrated’ magnetic states in neighboring electrons. Condensed matter physicists use the term ‘frustrated’ to describe a kind of magnet in which the spins fail to align into a stable magnetic order. Their unique properties are of interest in the development of quantum computing and high-temperature superconductivity. Image: Ames Laboratory.

Researchers at the US Department of Energy's Ames Laboratory have discovered and described the existence of a disordered electron spin state in a metal that may provide a unique pathway to finding and studying frustrated magnets. They report their discovery in a paper in Physical Review Letters.

Condensed matter physicists use the term ‘frustrated’ to describe a kind of magnet in which the electron spins fail to align into a stable magnetic order. In perfectly frustrated magnets known as spin liquids, the disordered magnetism persists even at very low temperatures, and the unique properties of these materials are of interest for the development of quantum computing and high-temperature superconductivity.

Typically, scientists search for this perfectly frustrated magnetic state in insulators. But Ames Laboratory researchers have now been able to define a ‘perfectly frustrated’ state in a metallic material, CaCo1.86As2.

"Perfectly frustrated systems, ones that really cannot resolve their magnetic states, are difficult to find in the first place, but even more so in a metal," said Rob McQueeney, a scientist at Ames Laboratory.

In insulating magnets, the interactions between spins that lead to frustration are set by the crystal structure of the lattice, and are relatively immutable. The discovery of this nearly perfectly frustrated metal provides a new avenue for tinkering with the magnetic interactions to achieve perfect frustration.

"Here, we have a little knob that we can tune. We know that some of these interactions that lead to frustration are mediated by conduction electrons, and we can tune a number of those very accurately – maybe you get a superconductor, maybe some other novel quantum state," said McQueeney. "There's a lot of promise there."

This story is adapted from material from Ames Laboratory, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.