Origin of Extreme Thermal Properties in Amorphous Diamond

Structural disorder hinders propagation of vibrational heat carriers, leading to intrinsically low thermal conductivity in amorphous solids. Recently, bulk amorphous diamond with hardness and elastic modulus exceeding those of its crystalline counterpart was synthesized and thermal conductivity of ~ 25 Wm^-1K^-1was reported at room temperature, higher than any other bulk amorphous solids and even some crystals. In this work, we explore the microscopic thermal transport mechanism in amorphous diamond through both computational and experimental techniques and discuss its implications in thermal transport in solids.