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arXiv · 1504.00259

A First-order Phase Transition to Metallic Hydrogen

Mohamed Zaghoo·Ashkan Salamat·Isaac F. Silvera
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Abstract

The insulator-metal transition in hydrogen is one of the most outstanding problems in condensed matter physics. The high-pressure metallic phase is now predicted to be liquid atomic from T=0 K to very high temperatures. We have conducted measurements of optical properties of hot dense hydrogen in the region of 1.1-1.7 Mbar and up to 2200 K. We observe a first-order phase transition accompanied by changes in transmittance and reflectance characteristic of a metal. The phase line of this transition has a negative slope in agreement with theories of the so-called plasma phase transition.

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Mohamed Zaghoo, Ashkan Salamat, Isaac F. Silvera. 2015-04-01. A First-order Phase Transition to Metallic Hydrogen. https://doi.org/10.1103/physrevb.93.155128

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