Nanowires that are superconducting above liquid nitrogen temperature have been produced for the first time, and their properties vary according to the diameter of the nanowires. The fact that they are superconducting over wider temperature ranges than other nanowires may make them uniquely suitable for some nanotech applications. From Laura Mgrdichian at PhysOrg.com “High-Temp Superconducting Nanowire System is First of its Kind“:
Scientists from the California Institute of Technology have, for the first time, created an array of nanowires that are superconducting at relatively high temperatures. This work, published recently in Nano Letters [abstract], could lead to the incorporation of superconducting nanowires into emerging nanotechnologies.
Researchers around the world have been working to create superconducting nanowires, but few studies have investigated the feasibility of nanowires made of high-critical-temperature (high-Tc) superconducting materials and, prior to this work, no such nanowires had been produced.
“We did not know whether high-Tc superconductivity could be maintained for very long, thin nanowires or whether their behavior would follow traditional superconductor models,” said CalTech chemist James Heath [one of the winners of the 2000 Foresight Nanotech Institute Feynman Prize in the Experimental category], the paper’s corresponding author, to PhysOrg.com.
He added, “High-Tc materials as nanostructures are also notoriously difficult to fabricate because their crystal structure and other properties must be maintained, and this is not easy to do.”
High-Tc materials are often more desirable than traditional superconductors because they function at temperatures “warmer” than the boiling point of liquid nitrogen, or 77 degrees Kelvin (about -321 degrees Fahrenheit). While still ultra-cold by everyday standards, these temperatures are easier to achieve in the laboratory because liquid nitrogen, which is commercially available and relatively easy to work with, can be used to cool them. This makes high-Tc materials more suitable for many applications.
—Jim
