摘要
Iron oxides are widely found as ores in Earth's crust and are also important constituents of its interiors.Their polymorphism,composition changes,and electronic structures play essential roles in controlling the structure and geodynamic properties of the solid Earth.While all-natural occurring iron oxides are semiconductors or insulators at ambient pressure,they start to metalize under pressure.Here in this work,we review the electronic conductivity and metallization of iron oxides under high-pressure conditions found in Earth's lower mantle.We summarize that the metallization of iron oxides is generally controlled by the pressure-induced bandgap closure near the Fermi level.After metallization,they possess much higher electrical and thermal conductivity,which will facilitate the thermal convection,support a more stable and thicker D′′layer,and formulate Earth's magnetic field,all of which will constrain the large-scale dynamos of the mantle and core.
作者
庄毓凯
胡清扬
Yukai Zhuang;Qingyang Hu(Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065,China;Center for High Pressure Science and Technology Advanced Research(HPSTAR),Beijing 100094,China)
基金
supported by the National Natural Science Foundation of China(Grant Nos.42150101 and 42150102)
supported by the CAEP Research Project(Grant No.CX20210048)
a Tencent Xplorer Prize(Grant No.XPLORER-2020-1013)。