This discovery, published in the journal Nature Physics, could form the basis for the development of new quantum devices, including ultra-precise sensors, energy-efficient computing systems, and innovative materials.
Researcher Tsimiao Si, a professor of physics and astronomy, said: "This is a fundamental step forward. Our research has shown that strong quantum effects can interact and create entirely new properties that open the way for future technologies."
Quantum criticality describes the behavior of electrons as they oscillate between different phases, such as water on the verge of freezing or boiling. Topology in quantum physics studies the stable configurations of the electron wave function, which remain conserved when the structure of matter changes. These phenomena were previously studied separately, with topology found in weakly interacting materials and criticality observed in systems with strongly bonded electrons.
Professor C’s team proposed a theoretical model that integrates these two effects, and showed that the strong interaction between electrons can induce topological behavior, creating a hybrid state.
"We were surprised that the same quantum criticality could generate topological effects under strong interactions," said Li Chen, a graduate student at Rice University and co-author of the research.
The phase diagram of CeRu₄Sn₆ material shows how the quantum state of the material changes under the influence of pressure and a magnetic field. In different regions of the diagram, electrons behave in different ways, creating new topological effects and quantum critical states that may be useful for future technologies.
Researchers at the Vienna University of Technology, led by Silke Paschen, confirmed the theoretical findings by studying a material with heavy fermions, where electrons behave as significantly larger particles due to strong interactions. The observed behavior matched the team's theoretical predictions, and the material exhibited signs of a novel topological quantum state.
The integration of quantum criticality and topology opens up vast possibilities for the development of quantum technologies. Topological properties give a system resistance to external disturbances, while criticality enhances quantum entanglement, making systems more sensitive and controllable. This is crucial for the development of sensors, superconductors, and low-power computing devices.
Professor C explained: "Our results cover a gap in condensed matter physics, where strong electronic interactions not only do not destroy topological properties but can create them, opening up a new case with practical importance for technology."
This discovery allows for the systematic research or design of materials that lie at a quantum critical point and are capable of forming topological structures. This approach gives scientists a tool to develop materials with predictable quantum properties and improved specifications for electronics and sensors.
C concluded by saying, "Understanding where to look for these effects gives us the ability to move from theory to real-world technologies based on fundamental quantum physics."
