Harvard Researchers Advance Superconductor Technology, Key for Quantum Computing
Harvard researchers, led by Philip Kim, have advanced superconductor technology by creating a high-temperature superconducting diode using cuprates. This innovative development is crucial for quantum computing and represents a significant step forward in manipulating and understanding exotic materials and quantum states.
Superconductors have fascinated physicists for decades, but their practical use has been limited by the low temperatures required to achieve their quantum-mechanical properties. However, a research team led by Harvard Professor of Physics and Applied Physics Philip Kim has demonstrated a new strategy for making and manipulating a widely studied class of higher-temperature superconductors, called cuprates, paving the way for engineering new and unusual forms of superconductivity in previously unattainable materials.
Using a uniquely low-temperature device fabrication method, Kim and his team have produced a promising candidate for the world’s first high-temperature, superconducting diode made out of thin cuprate crystals. This device could have significant implications for industries like quantum computing, which rely on challenging mechanical phenomena that are difficult to sustain.
“High-temperature superconducting diodes are, in fact, possible, without application of magnetic fields, and open new doors of inquiry towards exotic materials study,” said Philip Kim. The team’s experiments were led by S. Y. Frank Zhao, who engineered a clean interface between two extremely thin layers of the cuprate bismuth strontium calcium copper oxide, nicknamed BSCCO, using a cryogenic crystal manipulation method in ultrapure argon.
The team’s discovery has demonstrated electronic control over the interfacial quantum state and has effectively allowed them to create a switchable, high-temperature superconducting diode. This represents a groundbreaking demonstration of foundational physics that could one day be incorporated into pieces of computing technology, such as quantum bits.
The research was supported by the National Science Foundation, the Department of Defense, and the Department of Energy. The Harvard team worked with colleagues from the University of British Columbia and Rutgers University, whose teams previously performed theoretical calculations that accurately predicted the behavior of the cuprate superconductor in a wide range of twist angles. Additional theory developments were performed by the University of Connecticut.
This advancement in superconductor technology has significant potential for the future of quantum computing and could open up new avenues for understanding and manipulating exotic materials and quantum states.