Anomalous optical and electronic properties of dense sodium

作者：Lazicki A^*; Goncharov A F; Struzhkin V V; Cohen R E; Liu Z; Gregoryanz E; Guillaume C; Mao H K; Hemley Russell J

来源：Proceedings of the National Academy of Sciences, 2009, 106(16): 6525-6528.

DOI：10.1073/pnas.0902062106

• high pressure
• infrared reflectivity
• metal-insulator transition

Synchrotron infrared spectroscopy on sodium shows a transition from a high reflectivity, nearly free-electron metal to a low-reflectivity, poor metal in an orthorhombic phase at 118 GPa. Optical spectra calculated within density functional theory (DFT) agree with the experimental measurements and predict a gap opening in the orthorhombic phase at compression beyond its stability field, a state that would be experimentally attainable by appropriate choice of pressure-temperature path. We show that a transition to an incommensurate phase at 125 GPa results in a partial recovery of good metallic character up to 180 GPa, demonstrating the strong relationship between structure and electronic properties in sodium.

• 出版日期2009-4-21