The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understand...The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understanding of IH by introducing a new physical quantity,the IH admixture ratioα.Consequently,an exotic strategy of IH engineering in energy space can be proposed,i.e.,instead of changing t as commonly used,αcan be effectively tuned in energy space by changing the on-site energy difference(2Δ)between neighboring-layer states.In practice,this is feasible via reshaping the electrostatic potential of the surface by deposing a dipolar overlayer,e.g.,crystalline ice.Our first-principles calculations unveil that IH engineering via adjusting 2Δcan greatly tune interlayer optical transitions in transition-metal dichalcogenide bilayers,switch different types of Dirac surface states in Bi_(2)Se_(3)thin films,and control magnetic phase transition of charge density waves in 1H/1T-TaS_(2)bilayers,opening new opportunities to govern the fundamental optoelectronic,topological,and magnetic properties of vdW systems beyond the traditional interlayer distance or twisting engineering.展开更多
基金supported by the National Key R&D Program of China(Grant No.2022YFA1504000)the National Natural Science Foundation of China(Grant Nos.12088101,U2230402)+1 种基金the Tianjin Natural Science Foundation(Grant No.20JCZDJC00750)the Deutsche Forschungsgemeinschaft(DFG)(Grant No.EXC 2077)。
文摘The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understanding of IH by introducing a new physical quantity,the IH admixture ratioα.Consequently,an exotic strategy of IH engineering in energy space can be proposed,i.e.,instead of changing t as commonly used,αcan be effectively tuned in energy space by changing the on-site energy difference(2Δ)between neighboring-layer states.In practice,this is feasible via reshaping the electrostatic potential of the surface by deposing a dipolar overlayer,e.g.,crystalline ice.Our first-principles calculations unveil that IH engineering via adjusting 2Δcan greatly tune interlayer optical transitions in transition-metal dichalcogenide bilayers,switch different types of Dirac surface states in Bi_(2)Se_(3)thin films,and control magnetic phase transition of charge density waves in 1H/1T-TaS_(2)bilayers,opening new opportunities to govern the fundamental optoelectronic,topological,and magnetic properties of vdW systems beyond the traditional interlayer distance or twisting engineering.
