Plasmons on the edge ofMoS2nanostructures

Effect of edge plasmons on the optical properties of MoS2 monolayer flakes

“…The ideal structure is cut directly from the MoS 2 monolayer, but the S atoms forming the S 2 edge have been displaced closer to each other so that the edge configuration resembles that of an infinite MoS 2 nanoribbon [19]. This S 2 -edge configuration is similar to the relaxed one in Fig.…”

“…Depending on the growth conditions, the flakes favor different edge terminations or shapes [16,[25][26][27]. However, for alternative S-terminated edges, the 1D plasmons are expected to couple weaker to light [19] and they have not been reported in previous computational studies of Sterminated triangular flakes [28,29].…”

“…It is understood that the edges of the MoS 2 nanoclusters are catalytically active [11][12][13] and that this is due to the existence of metallic states present at certain edge configurations [14][15][16][17][18]. It has recently been shown that these states can lead to the formation of plasmons, i.e., quantized oscillations of electron gas plasma, along the edges of infinite MoS 2 nanoribbons [19]. This suggests that localized plasmon resonances could form at the edges of finite MoS 2 flakes.…”

“…This edge configuration is particularly interesting because the metallic edge state on the S 2 dimers supports a strong 1D edge plasmon [19]. Depending on the growth conditions, the flakes favor different edge terminations or shapes [16,[25][26][27].…”

“…The D 3h symmetry of the flake was enforced during the relaxation. The flake geometry was initialized by setting the edge S 2 dimers in a configuration resembling the corresponding edge of a MoS 2 ribbon [19] and then distorting the S 2 edge without breaking the D 3h symmetry. Then, the system was relaxed until the atomic forces were converged to less than 0.02 eV/Å.…”