The structure of liquid atomic hydrogen*

Atomic hydrogen, which forms at megabar pressures, is predicted to host a number of extreme characteristics, such as room temperature superconductivity [1], possibly coexisting with superfluid order [2]. Using a model based on first-principles calculations, we investigated the structure of liquid atomic hydrogen near the predicted melting line. Up to 1 TPa, the static structure factor exhibits a marked two-peak structure, which we associate with Friedel oscillations. The distinct intensity of this feature suggests that the metallic character of liquid atomic hydrogen is much more pronounced than that of other liquid metals.

[1] N. W. Ashcroft, "Metallic Hydrogen: A High-Temperature Superconductor?" Phys. Rev. Lett. 21, 1748 (1968)

[2] Babaev, E., Sudbø, A. & Ashcroft, "N. A superconductor to superfluid phase transition in liquid metallic hydrogen." Nature 431, 666–668 (2004)