Recently, the research team led by Sun Bo from the Tsinghua Shenzhen International Graduate School, in collaboration with their partners, has achieved a significant milestone by successfully synthesizing single crystals of metallic hexagonal tantalum nitride (θ-TaN) with ultra-high thermal conductivity through a high-temperature and high-pressure technique. This novel material boasts an impressive thermal conductivity of up to 502 W m⁻¹ K⁻¹ at room temperature, surpassing the long-established upper threshold for thermal conductivity in metallic substances and opening up fresh avenues for the exploration and development of cutting-edge thermal management materials. The remarkable thermal conductivity of this material primarily stems from its large acoustic-optical phonon energy gap and low electronic state density, which effectively minimize phonon-electron scattering. Moreover, the material also exhibits a high oxidation temperature and excellent thermal stability, showcasing a comprehensive set of advantages for advanced thermal management applications. The pertinent findings have been published in the esteemed journal National Science Review.