Researchers have demonstrated the ability to grow high-quality thin films of a recently discovered superconductor material called potassium tantalate (KTaO3). The researchers also discovered that the material retains its superconductive characteristics even when exposed to extremely high magnetic fields.
A superconductor is a material that can carry electricity without any resistance – meaning none of the energy is dissipated as heat, for example. Superconductive materials hold promise for making a variety of more efficient technologies, such as faster computer components and more energy-efficient power devices. However, the field faces significant challenges. For example, many superconductive materials lose their superconductivity when exposed to magnetic fields, which limits their potential applications.
The researcher says that their work here is important because not only have they demonstrated how to fabricate high quality KTaO3, but they have also shown that the material is capable of withstanding substantial magnetic fields without losing its desirable properties. Specifically, the researchers found that KTaO3 retains superconductivity even when exposed to magnetic fields up to 25 Tesla. This fundamental work is a necessary step toward the development of any potential applications for the material.
The researchers were able to “grow” KTaO3 using a technique called molecular beam epitaxy, which effectively creates two-dimensional (2D) thin films of the material on a substrate by laying molecule-thin layers on top of one another with atomic-level precision. The resulting thin films have extremely high quality, meaning the molecular structure of the material has very few defects.
These high-quality thin films are an ideal platform for studying the intrinsic properties of this materials system.
One such characterization study revealed that KTaO3 thin films remained superconductive when exposed to magnetic fields of up to 25 Tesla. To put that in context, the only place in the United States capable of generating a 25 Tesla magnetic field is the National High Magnetic Field Laboratory, which is where the researchers tested the material.
The research is covered in three journal articles. Most recently, the paper “Enhanced Critical Field of Superconductivity at an Oxide Interface” was published in Nano Letters.
News Source: NCSU
