New superconducting material packs an applied punch

Cross-section of MgB2 wire (20K JPG)

Collaborating with researchers at the Princeton Materials Institute, scientists in the College of Engineering's Applied Superconductivity Center (ASC) have made significant discoveries that may boost the potential of newly discovered high-temperature superconducting metal magnesium diboride (MgB2). The Applied Superconductivity Center has a broad multidisciplinary capability for doing both basic and applied studies of superconducting materials.

Earlier this year, Japanese scientists discovered that magnesium diboride superconducts up to 39 degrees Kelvin (minus 390 degrees Fahrenheit), almost twice the temperature of any other metallic superconductor. Just a short while later, ASC researchers David Larbalestier, Eric Hellstrom, Susan Babcock and Chang-Beom Eom overcame another challenge when they found evidence that the material can transport high electrical currents because its grain boundaries do not obstruct current flow. Recently, Eom discovered new evidence that alloying enables magnesium diboride to carry 100,000 amps of current per square centimeter in very strong magnetic fields (10 tesla) and withstand twice as high a magnetic field as the current commercially used superconducting material, niobium-titanium.

In addition, UW-Madison physics Professor Mark Rzchowski's group is studying the basic physics of the superconducting mechanism, while materials science Professor Susan Babcock's team is studying its atomic structure using transmission electron microscopy.