2013/08/12 by Yongkyung Kwon, Kwon, Yongkyung, Hyeondeok Shin +3
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Other Condensed Matter (cond-mat.other) #cond-mat.mtrl-sci #cond-mat.other
paper · pdf · doi:10.48550/arxiv.1308.2556
5 pages, 4 figures, submitted to Physical Review Letters
arxiv created 2013/08/12 · arxiv updated 2013/08/13
Path-integral Monte Carlo calculations were performed to study the adsorption of 4He atoms on α-graphyne. We find that one 4He atom can be embedded onto the in-plane center of each hexagon of the graphyne. In the first 4He layer above the 4He-embedded graphyne surface, a Mott insulating state was observed at the areal density of 0.0706 Å-2 with three 4He atoms occupying each hexagonal cell while the helium atoms form a commensurate triangular solid at a density of 0.0941 Å-2. Here we show that the Ising pseudo-spin symmetry introduced for two degenerate configurations of three 4He atoms in a hexagonal cell can be broken by additional 4He atoms placed at the hexagon vertices and the Mott-insulator to commensurate-solid transition is a transition from a nonmagnetic spin liquid of frustrated antiferromagnets to a spin-aligned ferromagnet under a particle-induced pseudo-magnetic field.