"Recombinant" materials achieve "mixing" of physical properties, and a new superconductor with chiral structure is made

Researchers at Tokyo Metropolitan University in Japan have created a new superconductor with a chiral crystal structure by mixing two materials. The new platinum-iridium-zirconium compound transforms into a superconductor below 2.2K, and its chiral crystal structure can be observed using X-ray diffraction. This technical solution is expected to accelerate the discovery and understanding of new exotic superconducting materials. The relevant paper was published in the latest issue of the Journal of the American Chemical Society.

Combining achiral superconducting materials and chiral non-superconducting materials in different element ratios to create new compounds with properties of both.
Image credit: Tokyo Metropolitan University

Scientists want to understand how the exotic properties of superconducting materials arise from their structure and how to control the structure to obtain desired properties. One interesting research development is the question of chirality. Many structures have chirality, a property that means they cannot be superimposed on their mirror image. The effect of chirality in superconductors can make superconductors more robust when exposed to high magnetic fields.

The Tokyo Metropolitan University team introduced a completely new method to search for chiral compounds. Instead of combing through a list of compounds, they mixed two compounds with known physical properties. One is a platinum-zirconium compound with superconductivity but no chirality, and the other is an iridium-zirconium compound with chirality but no superconductivity. Combining the two compounds in different element ratios can effectively "mix and match" physical properties, thereby proposing a new material that has both a chiral crystal structure and superconductivity.

The team first studied different mixture ratios and found that in about 80% iridium inclusions, the proportion of chiral crystal structures increased rapidly at room temperature. When the sample was cooled to low temperatures, they were able to confirm superconductivity up to around 85%. This left a "small window" in which both chirality and superconductivity can appear. Obviously, their new compound is a superconductor with a chiral structure.

The team also confirmed that superconductivity was generated in the bulk, rather than from the surface. Their work demonstrates the potential of the "mix and match" approach to create new exotic superconductors.

Why are scientists committed to exploring superconductors with chiral structures? Chirality, as the name suggests, is like our left and right hands. Although they look the same, they cannot overlap into one. The chirality phenomenon is widespread and can be said to be a basic property of nature. Superconductivity is one of the most concerned phenomena in physics. For a long time, the superconducting materials verified by scientists have been non-chiral, and chirality and superconductivity are rarely found in the same material at the same time. This is not good news for the research and development of superconductors, because most materials have chirality. The unification of the two may be the key to creating superconductors in the future that greatly improve electricity efficiency.