Quantum honey from black holes

Overview

Researchers of the Cluster of Excellence ct.qmat – Complexity and Topology in Quantum Matter have proposed a new quantum material in which electrons move as a viscous fluid – like a kind of quantum honey. If scientists succeed in producing the material in sufficient purity, the effect will be three times stronger than in the “miracle material” graphene. The low resistance of this electron liquid could open up new perspectives for microelectronics and storage media. Additionally, magnetic fields can be switched on and off with precision by vortex formation in this fluid. The researchers have published their research results in the journal Nature Communications.

Combining different fields of research
The study authors are Professor Johanna Erdmenger, who holds the Chair of Theoretical Physics III at the University of Würzburg (JMU), and Professor Ronny Thomale, who holds the Chair of Theoretical Physics I. Erdmenger has many years of research experience in black hole physics; Thomale has specialised in solid state physics. In the Cluster of Excellence ct.qmat, a research collaboration of scientists from the University of Würzburg and TU Dresden, the two researchers have combined the theoretical foundations of their respective research disciplines for the first time. Their findings could create entirely new opportunities in materials research.

When designing future electronics, one focus of interest is the transport properties of electrons. Scientists aim at finding materials that conduct electricity more quickly and efficiently. Already back in the 90ies, they discovered that electrons behave as fluids at certain temperatures and densities in electrical conductors, showing collective behaviour. Until then, it had been commonly believed that electrons move individually through an atomic lattice.

Honey flowing through atomic lattices
The researchers of the Cluster of Excellence ct.qmat have now discovered that electrons in a certain quantum material have much stronger bonds than previously known: "The bonds between the electrons in our quantum material are three times stronger than in graphene, for example. So you can think of the electron fluid as a kind of honey that flows through the atomic lattice without being affected by it," Johanna Erdmenger explains.

The quantum material in which this effect can occur is the mineral "Herbertsmithite" – however, in modified form: "We would have to replace the zinc atoms with scandium atoms," the physicist says. If this works, we would obtain a very special new material that would even allow vortex formation in the electron fluid.”

This finding was only possible because the research teams of Professor Erdmenger and Professor Thomale integrated previously separate theories from quantum gravity and solid state physics. To achieve this, the physicists equated the temperature of black holes, the so-called "Hawking temperature", with the temperature of electrons in the quantum material. Their research has led to a concrete prediction of a quantum material in which honey-type liquid behaviour can occur: "Scandium-Herbertsmithite" (Sc-Hb) with trivalent scandium atoms instead of bivalent zinc.