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arXiv · 1610.01634

Observation of the Wigner-Huntington Transition to Solid Metallic Hydrogen

Ranga Dias·Isaac F. Silvera
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Abstract

We have studied solid hydrogen under pressure at low temperatures. With increasing pressure we observe changes in the sample, going from transparent, to black, to a reflective metal, the latter studied at a pressure of 495 GPa. We have measured the reflectance as a function of wavelength in the visible spectrum finding values as high as 0.90 from the metallic hydrogen. We have fit the reflectance using a Drude free electron model to determine the plasma frequency of 30.1 eV at T= 5.5 K, with a corresponding electron carrier density of 6.7x1023 particles/cm3, consistent with theoretical estimates. The properties are those of a metal. Solid metallic hydrogen has been produced in the laboratory.

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Ranga Dias, Isaac F. Silvera. 2016-10-05. Observation of the Wigner-Huntington Transition to Solid Metallic Hydrogen. https://doi.org/10.1126/science.aal1579

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