Scientists have successfully transformed germanium, a critical semiconductor material, into a superconducting state for the first time. This significant achievement could enhance the performance of electronic devices and facilitate advancements in quantum technology. A collaborative team from New York University, the University of Queensland, and other international institutions reached this milestone by enabling germanium to conduct electricity with zero resistance at a temperature of 3.5 Kelvin (approximately -453 degrees Fahrenheit).
According to Javad Shabani, a physicist at New York University and director of the university’s Center of Quantum Information Physics, this breakthrough has the potential to revolutionize a wide range of consumer products and industrial technologies. He noted, “Establishing superconductivity in germanium, which is already widely used in computer chips and fiber optics, can potentially revolutionize scores of consumer products and industrial technologies.”
For decades, researchers have sought to achieve superconductivity in semiconductors like germanium and silicon. Superconductors allow electrical currents to flow indefinitely without energy loss, which could vastly improve the speed and efficiency of electronic devices. Despite their stability and flexibility, the challenge has been to manipulate the atomic structure of these materials to achieve the necessary electron behavior for superconductivity.
Precision Doping Paves the Way
The research team accomplished this by introducing gallium into germanium through a method known as doping. This process typically destabilizes the crystal structure when excessive gallium is added, hindering superconductivity. The breakthrough came through the use of molecular beam epitaxy, a precise technique that allows for the growth of ultra-thin crystal layers.
Julian Steele, a physicist at the University of Queensland, explained, “Rather than ion implantation, molecular beam epitaxy was used to precisely incorporate gallium atoms into the germanium’s crystal lattice.” This method enabled the researchers to achieve a stable structure while incorporating gallium atoms at unusually high concentrations.
Advanced X-ray analysis confirmed that although the crystal’s shape changed slightly, it remained stable and capable of conducting electricity without resistance.
Implications for Quantum Technologies
The ability to create superconducting germanium could significantly impact technologies that depend on seamless interactions between semiconducting and superconducting regions, such as quantum circuits and sensors. Peter Jacobson, another physicist involved in the study, stated, “These materials could underpin future quantum circuits, sensors, and low-power cryogenic electronics, all of which need clean interfaces between superconducting and semiconducting regions.”
Shabani further emphasized the importance of modifying crystal structures to unlock new electronic properties. “This works because group IV elements don’t naturally superconduct under normal conditions, but modifying their crystal structure enables the formation of electron pairings that allow superconductivity,” he said.
The findings were published in the journal Nature Nanotechnology, underscoring the significance of this research in the ongoing quest to enhance materials for next-generation electronic and quantum technologies. The ability to harness superconductivity in widely used materials like germanium could lead to a new era in electronics, making devices faster, more efficient, and capable of supporting the demands of emerging technologies.