[14p-D215-1~7] 【CS.5】 7.4 量子ビーム界面構造計測、9.5 新機能材料・新物性のコードシェアセッション

▲ [14p-D215-5] Ground state determination of LiVX₂ system using Diffusion Monte Carlo

〇(D)Genki Imam Prayogo¹、Aleksey Ushakov²、Tom Ichibha³、Kenta Hongo^1,5,6、Sergey Streltsov²、Ryo Maezono^1,4 (1.JAIST、2.Inst. Met. Phys.、3.ORNL、4.RIKEN、5.NIMS、6.PRESTO, JST)

キーワード：Diffusion Monte Carlo, frustrated antiferromagnet

The LiVX₂ system (X: O, S, Se) is an example of a Heisenberg antiferromagnet with the geometrical frustration existing on the triangular lattice of its vanadium layer. While LiV(O,S)₂ has been observed to host a VBS state at low temperature, indicated by a metal-to-insulator transition and trimerization of the vanadium lattice, LiVSe₂ was not found to exhibit such transition. With its strong electronic correlation, methods based on one-body theory, such as DFT, often failed to correctly describe its properties, as was found in our preliminary calculations. We employed a new approach based on Diffusion Monte Carlo, which is based on many-body wave function, thus expected to correct for this. We performed a static energetic comparison between the trimerization structures, in both unpolarized and collinear spin-polarized formalization, as well as charge density analysis in the frustrated vanadium layer, benchmarking both approach against experimental data.