Ultrasound elasticity of diamond at gigapascal pressures
Qingyang Hu, Baosheng Li, Xiang Gao, Yan Bi, Lei Su, Ho‐kwang Mao
Abstract
Significance The exceptional hardness of diamond makes it an unmatched material for compressing and mechanical processing. For the same reason, compressing diamond and measuring its high-pressure, elastic properties turns out to be a very challenging task. Combining the ultrasonic interferometry and multianvil press, we extended the research forefront of diamond’s elasticity from kilobar to gigapascal pressures and showed that diamond becomes increasingly compressible, reaching agreement with theory. The results also point out the unique potential of diamond in providing an accurate, absolute pressure standard up to the terapascal region, which will be the basis cornerstone of the extensive, high-pressure sciences.