Physicists Discover Mechanism Behind Oscillating Superconductivity
Physicists have made a breakthrough in understanding the mechanism responsible for oscillating superconductivity, a peculiar behavior observed in certain materials like high-temperature superconductors. The discovery of this mechanism, termed pair-density waves, was achieved through an investigation of structures known as Van Hove singularities. The findings were published in the esteemed journal Physical Review Letters.
The study was led by Luiz Santos, an assistant professor of physics at Emory University, who explained the significance of the research, stating, “We discovered that structures known as Van Hove singularities can produce modulating, oscillating states of superconductivity. Our work provides a new theoretical framework for understanding the emergence of this behavior, a phenomenon that is not well understood.”
The research team was comprised of Pedro Castro, a graduate student at Emory University and the first author of the study, Daniel Shaffer, a postdoctoral fellow, and Yi-Ming Wu from Stanford University.
Superconductivity, the ability of certain materials to conduct electricity without resistance, has fascinated scientists for over a century since its discovery in 1911. However, it wasn’t until 1957 that scientists developed an explanation for this phenomenon. At low temperatures, electrons in certain materials can form pairs that create a collective state, allowing for the efficient flow of electrical current.
The potential applications of superconductivity are vast, including the possibility of transferring electric current without energy loss. This breakthrough could revolutionize various fields, from energy transmission to transportation systems.
While superconductivity has already found practical applications, such as magnetic resonance imaging (MRI) machines and magnetic levitation trains, scientists continue to explore this area of research. Santos’ particular interest lies in studying the interactions between electrons that lead to unconventional forms of superconductivity.
The researchers discovered that Van Hove singularities, where multiple electronic states come close in energy, have the right conditions to seed oscillating superconductivity. This finding provides a solid foundation for experimentalists to further investigate this intriguing behavior.
Santos emphasized the broader implications of their study, stating, “As theoretical physicists, we want to be able to predict and classify behavior to understand how nature works. Then we can start to ask questions with technological relevance.”
The prospective applications of this research extend beyond what was originally envisioned by the discoverer of superconductivity, Heike Kamerlingh Onnes. Santos added, “But everything we learn about the world has potential applications.”
The study was funded by the U.S. Department of Energy’s Office of Basic Energy Sciences, underlining the significance of this research in advancing our understanding of superconductivity and its potential technological applications.
Reference: “Emergence of the Chern Supermetal and Pair-Density Wave through Higher-Order Van Hove Singularities in the Haldane-Hubbard Model” by Pedro Castro, Daniel Shaffer, Yi-Ming Wu, and Luiz H. Santos, 11 July 2023, Physical Review Letters.
DOI: 10.1103/PhysRevLett.131.026601