Researchers detect exotic superionic phase in iron hydride mimicking inner core
Scientists at Science Tokyo used diamond-anvil cells with laser heating to study iron hydride under conditions similar to Earth's inner core. They found experimental evidence of a superionic state, where some atoms move like a liquid while others remain solid. This provides new clues about the composition and behavior of Earth's deep interior.
This study probes iron hydride under extreme pressures and temperatures, replicating conditions thought to exist thousands of kilometers beneath our feet. The diamond-anvil cell, a device capable of squeezing materials to millions of atmospheres, combined with laser heating, allows researchers to mimic the inner core’s punishing environment. The discovery of a superionic phase—where hydrogen atoms diffuse like a liquid through a solid iron lattice—offers a new lens on how seismic waves travel through Earth’s deep interior. Such findings refine models of core composition, density, and thermal conductivity, potentially explaining longstanding anomalies in geophysical observations. While the work is experimental, it underscores how laboratory physics can illuminate planetary processes otherwise inaccessible to direct study.
This finding could reshape how geophysicists interpret seismic data, offering a more nuanced picture of the inner core’s structure and dynamics. It may influence models of Earth’s thermal evolution and magnetic field generation, with implications for understanding planetary habitability. Researchers in solid-state physics and planetary science could build on this work, while educators might use it to illustrate extreme-matter behavior. Society benefits indirectly through improved knowledge of our planet’s deep history, though practical applications remain distant. The result also highlights the value of fundamental science in answering questions about Earth’s origins.