Engineers wrestling with heat densities in AI accelerators now have a new variable to consider: an electric field applied to a specialized ceramic can triple its thermal conductivity, according to a study from the Department of Energy's Oak Ridge National Laboratory and collaborators that drew renewed attention when ScienceDaily redistributed the findings in July 2026. The result, published in PRX Energy in January 2026 by researchers at ORNL, The Ohio State University, and Amphenol Corporation, was not predicted by prior work. Earlier experiments on bulk ferroelectric materials had produced modest thermal conductivity improvements of 5 to 10 percent. The new measurements revealed a gain close to 300 percent — roughly 30 to 60 times larger than anything previously documented in a bulk solid material under an external electric field. The ORNL team demonstrated that an external field can tune thermal conductivity dynamically, in a material already installed, without changing its composition. The carriers of heat in a ceramic are phonons, and the researchers changed their lifetime. "Earlier work on bulk ferroelectric materials achieved modest improvements in thermal conductivity of 5 percent to 10 percent, while the new measurements reveal an enhancement close to 300 percent — mainly because the phonons are able to travel much longer before they stop," said Michael Manley, an ORNL senior researcher who designed and led the inelastic neutron scattering experiments. The ceramic material belongs to a class called relaxor-based ferroelectrics, where nanoscale clusters called polar nanoregions