A multi-year collaboration between electrical and materials science engineers at the University of Wisconsin-Madison has resulted in a promising new electron emission cathode material, a key component in modern vacuum electronics. The new material could improve components used in satellite communications, electron microscopy and other high-power, high-frequency applications.
In a paper posted June 5, 2024 by the journal APL Materials, the team demonstrates that the material, strontium vanadium oxide, exhibits a low work function, making it an ideal material for electron emission cathodes. The researchers include John Booske, a professor emeritus of electrical and computer engineering; Dane Morgan, a professor of materials science and engineering; Ryan Jacobs, a staff scientist; and Md Sariful Sheikh, a postdoctoral researcher.
For much of the 20th century, vacuum electronics, including the well-known vacuum tubes, were a critical—and highly visible—technology. In particular, glass vacuum tubes were key components in radios, televisions, low power amplifiers and early computers before smaller, mass-manufactured semiconductor-based transistors replaced them. But modern versions of vacuum tubes are still with us (one is hidden in your microwave oven), and are critical to high-power, high-frequency and/or high-voltage applications that challenge traditional semiconductor devices. These applications include radar, high power satellite communications, industrial (and domestic) microwave heating, electron microscopes, and scientific research applications.