Abstract
Path-integral Monte Carlo calculations have been carried out to investigate physical properties of a He4 monolayer adsorbed on a single 6,6,12-graphyne sheet, which is one of the graphyne families possessing a rectangular symmetry. To characterize elusive quantum phases of an adsorbed He4 monolayer on 6,6,12-graphyne, we model the He4-graphyne interaction by the pairwise sum of empirical He4-C interatomic potentials. At partially filled He4 coverages, we identify three commensurate solids of the C3/4,C4/4, and C6/4 structures from the two-dimensional density distribution. These solids show the rectangular symmetry inherited from the symmetry of 6,6,12-graphyne, which were confirmed with the analysis of their static structure factors. At high helium coverages near its completion, the He4 monolayer is predicted to exhibit a transition from a rectangular commensurate structure to a triangular incommensurate structure, after going through inhomogeneous structures mixed with domains of triangular and rectangular orderings. This symmetry-changing transition has not been observed in He4 monolayers adsorbed on other carbon substrates.
| Original language | English |
|---|---|
| Article number | 024113 |
| Journal | Physical Review B |
| Volume | 99 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jan 30 2019 |
| Externally published | Yes |
Funding
This work was supported by Konkuk University in 2015. We also acknowledge the support from the Supercomputing Center/Korea Institute of Science and Technology Information with supercomputing resources including technical support (KSC-2017-C3-0033). This work was supported by Konkuk University in 2015. We also acknowledge the support from the Supercomputing Center/Korea Institute of Science and Technology Information with supercomputing resources including technical support (KSC-2017-C3-0033).
| Funders | Funder number |
|---|---|
| Konkuk University | |
| Korea Institute of Science and Technology Information | KSC-2017-C3-0033 |