Elena Hassinger, an expert in low-temperature physics who works at ct.qmat - Complexity and Topology in Quantum Matter (a joint initiative of the universities of Würzburg and Dresden), conducts research that has been synonymous with extreme cold. In 2021, she discovered the unconventional superconductor cerium rhodium arsenic (CeRh2As2). Superconductors typically have only one resistanceless electron transport phase, which occurs below a certain critical temperature. However, according to the academic journal Science, CeRh2As2 is the only quantum material so far to possess two specific superconducting states.
Unconventional superconductor CeRh2As2: quantum superstar
Lossless current conduction in superconductors has been a core focus of solid-state physics for decades and has emerged as an important prospect for future power engineering. The second superconducting phase found in CeRh2As2 results from an asymmetric crystal structure around the cerium atoms (the rest of the crystal structure is completely symmetrical), making this compound a prime candidate for topological quantum computing. Hassinger plans to expand her research into other quantum materials with similar unusual structural properties, hoping to achieve topological superconductivity at higher temperatures.
The European Research Council awarded Hassinger 2.7 million euros ($2.96 million) for her project "Exotic quantum states with locally broken inversion symmetry under extreme conditions - Ixtreme." In the next five years, she plans to use the funds to further study the superconducting "Miracle"-CeRh2As2 at the Dresden Laboratory, discover related quantum materials, and contribute to major breakthroughs in the field of topological quantum computing.
"If we could confirm my theoretical predictions of the topological surface states of cerium-rhodium-arsenic compounds in the laboratory, this would pave the way for the creation of topological quantum bits (qubits). This would be a huge advance," explains Hassinger.
Topological qubits are known for their stability, providing quantum states that are much more stable than non-topological qubits. One of the biggest challenges in current research is developing a method to maintain 1,000 qubits simultaneously.
Achieving this would enable quantum processors to complete tasks in minutes that would take conventional supercomputers years. That's why the bright minds at ct.qmat are focusing on the research of topological quantum materials.
To study the unconventional superconductor cerium rhodium arsenic, Hassinger first needed a cryostat to cool samples of the material below 0.35 Kelvin (-272.8 degrees Celsius).
"This machine costs more than 1 million euros," she revealed. "When the sample is cold enough, it will withstand strong pressure and an ultra-strong magnetic field of up to 18 Tesla, far exceeding the 0.1 Tesla magnetic field of a typical horseshoe magnet. Making these high-voltage magnetic field measurements can take several months and requires Precise adjustments are made every day. Her goal is to carefully study the second superconducting phase of CeRh2As2 to conclusively prove that this material is a topological superconductor. If the research is successful, this "miracle material" will not only enable lossless electron conduction, but also have powerful topological surface states that may be used in quantum computing operations.
"The European Research Council funds promising pioneering research through the European Research Council Consolidator Grant (ERCConsolidatorGrant). With this new grant, Hassinger is expected to be the first to experimentally identify its exotic quantum state and to discover relevant quantum states in similar materials at higher temperatures," says Professor Matthias Vojta, spokesman for ct.qmat Dresden. "We are delighted to have her become a member of our ct.qmat research family."
Compiled source: ScitechDaily