Abstract

A supersolid is a mysterious and puzzling state of matter which created a vigorous debate on its existence among physicists over 60 years. Elusive nature of a supersolid phase stems from the coexistence of the long-range order and superfluidity. Here we report computational evidence of the supersolid phase of deuterium under pressure (p >500 GPa) and low temperature (T ~ 1.0K). An active exchange process of deuterium atoms, treated by Bosonic Feynman path integral molecular dynamics, develops into a highly concerted manner by which the system yet preserves the crystalline symmetry. Soft core interactions of deuterium allow to form densely packed metallic solid, and this pressurised environment leads to favour in exchange. At zero temperature limit, the Bose-Einstein condensation is observed as the permutation probability of N deuterium atoms approaches to 1/N. Our study provides concrete evidence for the existence of supersolid phase in high-pressure deuterium and could provide insights on the future investigation of supersolid in real materials.