Researchers have developed a groundbreaking technique using terahertz pulses of light to shed light on the mysterious disorder within superconductors, paving the way for a deeper understanding of these remarkable materials.
Probing Disorder’s Impact
Disorder is an essential ingredient of the strange properties of high-temperature superconductors, but it has proven very challenging to study. But conventional methods such as scanning tunneling microscopy are useful only at very low temperatures, so they have been able to provide only limited and controversial evidence on how disorder affects superconductivity close to the transition temperature.
The answer is provided by the novel approach of a research team from the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Germany, supported theoretically by a group at Brookhaven National Laboratory in the United States. This is climbing to higher frequencies that are typically probed by special versions of nuclear magnetic resonance (such as high frequency ESR), adapted for the terahertz range, and called angle-resolved two-dimensional terahertz spectroscopy (2DTS).
Unlocking Superconductors’ Secrets
First, the researchers were able to test La1 cuprate superconductor with this new method. 83Sr0. 17CuO4, known for its impenetrability to light. The angle resolved 2DTS approach enabled them to separate terahertz nonlinearities in the form of emitted directions for the first time.
The team was surprised to find that the degree of disorder in superconducting transport is much smaller than the corresponding disorder in superconducting gap diagnosed with scanning microscopy experiments. They also found that the disorder persisted up to a high 70% of the transition temperature, far warmer than intuition would suggest for such complicated materials.
The versatility of the angle-resolved 2DTS technique also suggests it may be suitable to explore transient metamaterial states that are too evanescent for typical disorder probes. This accomplishment will pave the way for a more profound comprehension of the mysteries of cuprate superconductors and other quantum materials.
Conclusion
This discovery by the research team that terahertz pulses of light can untangle the twisty disorder in a suite superconductor is pretty freaking awesome!! This breakthrough was reached by transcending the limits of traditional techniques and is providing new views on the intricate correlation between disorder and superconductivity, enabling new exciting studies in material science and condensed matter physics.
