Abstract
We revisited the phase diagram of the second layer of on top of graphite using quantum Monte Carlo methods. Our aim was to explore the existence of the novel phases suggested recently in experimental works, and determine their properties and stability limits. We found evidence of a superfluid quantum phase with hexatic correlations, induced by the corrugation of the first Helium layer, and a quasi-two-dimensional supersolid corresponding to a registered phase. The commensurate solid was found to be unstable, while the triangular incommensurate crystals, stable at large densities, were normal.
- Received 18 February 2020
- Revised 6 May 2020
- Accepted 12 May 2020
DOI:https://doi.org/10.1103/PhysRevLett.124.205301
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