Scientists discover boron arsenide beats diamond in heat transfer

Researchers at the University of Houston have discovered that boron arsenide (BAs), a synthetic crystal, surpasses diamond in thermal conductivity, achieving values above 2,100 W/mK at room temperature. This finding challenges the long-held belief that diamond is the best isotropic heat conductor and suggests that existing theoretical models need revision, as previous calculations—factoring in four-phonon scattering—had capped BAs’s conductivity at 1,360 W/mK. The breakthrough was made possible by producing ultra-pure BAs crystals through refined synthesis techniques, overcoming limitations caused by impurities in earlier samples. Beyond its record-breaking heat conduction, boron arsenide also exhibits promising semiconductor properties, including a wider band gap, higher carrier mobility, and compatibility with chip integration due to its thermal expansion coefficient. These combined attributes make BAs a strong candidate to outperform silicon in electronics, offering potential improvements in thermal management for devices ranging from smartphones to data centers and high-performance computing systems. Supported by a National