Low temperature phase diagram of hydrogen at pressures up to 380 GPa. A possible metallic phase at 360 GPa and 200 K

Research paper by M. I. Eremets, I. A. Troyan, A. P. Drozdov

Indexed on: 18 Jan '16Published on: 18 Jan '16Published in: Physics - Materials Science


Two new phases of hydrogen have been discovered at room temperature in Ref.1: phase IV above 220 GPa and phase V above ~270 GPa. In the present work we have found a new phase VI at P~360 GPa and T<200 K. This phase is likely metallic as follows from the featureless Raman spectra, a strong drop in resistance, and absence of a photoconductive response. We studied hydrogen at low temperatures with the aid of Raman, infrared absorption, and electrical measurements at pressures up to 380 GPa, and have built a new phase diagram of hydrogen.