• Wed. Nov 29th, 2023

    Critical Thought

    Critical thoughts on quantum technologies

    New Insights on Electron Coupling in Quantum Materials

    ByByron Bekker

    Nov 17, 2023
    New Insights on Electron Coupling in Quantum Materials

    Rice University physicists have made a groundbreaking discovery regarding quantum materials. They have found that immutable topological states, which have significant potential for quantum computing, can be entangled with other manipulable quantum states. This finding opens up new possibilities in the field of condensed matter physics.

    The researchers at Rice University conducted a study on the behavior of electrons in a specific type of crystal lattice. They observed that in this lattice, the strongly coupled behavior of electrons in d atomic orbitals mimics the behavior of f orbital systems found in heavy fermions. This unexpected similarity provides a connection between two subfields of condensed matter physics that have traditionally focused on different emergent properties of quantum materials.

    In topological materials, patterns of quantum entanglement result in “protected” states that are highly desirable for applications in quantum computing and spintronics. On the other hand, strongly correlated materials exhibit various phenomena such as unconventional superconductivity and continuous magnetic fluctuations. By discovering the entanglement of electrons in d atomic orbitals and their interaction with frustrated electrons, the researchers have shed light on the relationship between these two types of materials.

    The study involved building and testing a quantum model to explore electron coupling in a lattice arrangement known as “frustrated” lattice, commonly found in metals and semimetals. The lattice features “flat bands,” where electrons become stuck and strongly correlated effects are amplified. Through their research, the scientists demonstrated that electrons in d atomic orbitals can become part of larger molecular orbitals shared by multiple atoms. This entanglement of electrons in molecular orbitals results in strongly correlated effects similar to those observed in heavy fermion materials.

    Although f-electron systems are known to host clean examples of strongly correlated physics, they are not practical for everyday use due to their low-temperature requirements. On the other hand, d-electron systems exhibit efficient coupling even in the presence of a flat band. This means that the f-electron-like physics can be achieved at much higher temperatures, potentially up to room temperature. This opens up new avenues for practical applications of strongly correlated physics.

    The implications of this research are significant. Quantum physicist Qimiao Si, one of the co-authors of the study, plans to further validate a theoretical framework for controlling topological states of matter. By understanding the mechanisms of electron coupling in quantum materials, scientists can develop new strategies for manipulating and harnessing their properties.

    This study provides a fresh perspective on the behavior of electrons in quantum materials and offers insight into the potential of topological states for practical applications. Further research in this area could lead to advancements in quantum computing, spintronics, and other fields.


    Q: What are topological states?
    A: Topological states refer to quantum states in materials that exhibit patterns of entanglement and possess “protected” properties.

    Q: What are strongly correlated materials?
    A: Strongly correlated materials are materials in which the behavior of electrons is strongly influenced by their interactions with each other.

    Q: What is quantum entanglement?
    A: Quantum entanglement is a phenomenon in which two or more particles become correlated and share information across vast distances.

    Q: What are heavy fermions?
    A: Heavy fermions are a class of materials that exhibit strong electron-electron interactions and unconventional behavior, such as high-temperature superconductivity.

    Q: What is a flat band?
    A: A flat band refers to a state in a lattice arrangement where electrons become stuck, resulting in enhanced strongly correlated effects.

    – Science Advances (2023). DOI: 10.1126/sciadv.adg0028