The rapid magnetic recovery process(MRP)after photoexcitation is crucial for efficient information recording in magnets but is often impeded by insufficient spin flip channels.Using time-domain ab initio nonadiabatic ...The rapid magnetic recovery process(MRP)after photoexcitation is crucial for efficient information recording in magnets but is often impeded by insufficient spin flip channels.Using time-domain ab initio nonadiabatic molecular dynamics including spin-orbital coupling(SOC),we investigate MRPin a CrI_(3) ferromagnetic monolayer and find that defects can accelerate this process.In defect-free CrI_(3),MRP is slow(400 fs)due to weak SOC between spin-majority and spin-minority valence band edges,notably limiting spin flips during relaxation.Intrinsic vacancy defects(VI and V_(Cr)),particularly the V_(Cr) defect,disrupt the system’s rotational symmetry by extending their states asymmetrically to bulk I ions.The lowered symmetry significantly enhances SOC near the valence band edges and speeds up MRP to 100 fs by promoting spin flips.This study uncovers the origins of slow MRP in CrI_(3) monolayer and highlights defect engineering as a promising strategy to improve MRP for optically excited spintronic devices.展开更多
基金sponsored by the Natural Science Foundation of Henan, Henan Province Outstanding Youth Science Foundation (Grants No. 252300421215)Key Scientific Research Project of Higher Education Institutions in Henan Province - Basic Research Program (Grants No. 25ZX005)National Natural Science Foundation of China (Grants No. 12274114).
文摘The rapid magnetic recovery process(MRP)after photoexcitation is crucial for efficient information recording in magnets but is often impeded by insufficient spin flip channels.Using time-domain ab initio nonadiabatic molecular dynamics including spin-orbital coupling(SOC),we investigate MRPin a CrI_(3) ferromagnetic monolayer and find that defects can accelerate this process.In defect-free CrI_(3),MRP is slow(400 fs)due to weak SOC between spin-majority and spin-minority valence band edges,notably limiting spin flips during relaxation.Intrinsic vacancy defects(VI and V_(Cr)),particularly the V_(Cr) defect,disrupt the system’s rotational symmetry by extending their states asymmetrically to bulk I ions.The lowered symmetry significantly enhances SOC near the valence band edges and speeds up MRP to 100 fs by promoting spin flips.This study uncovers the origins of slow MRP in CrI_(3) monolayer and highlights defect engineering as a promising strategy to improve MRP for optically excited spintronic devices.
