过渡金属硫族化合物(Transition metal chalcogenides,TMCs)因具有丰富的晶体结构和不寻常的电子特性呈现出有趣的物理现象,引起了人们的持续关注。重点介绍了过渡金属二硫化物(Transition metal dichalcogenides,TMDCs)中电荷密度波(Ch...过渡金属硫族化合物(Transition metal chalcogenides,TMCs)因具有丰富的晶体结构和不寻常的电子特性呈现出有趣的物理现象,引起了人们的持续关注。重点介绍了过渡金属二硫化物(Transition metal dichalcogenides,TMDCs)中电荷密度波(Charge density wave,CDW)和超导电性(Superconductivity,SC)的最新重要发现,系统分析和比较了TMDCs的晶体和能带结构,总结了掺杂和高压对TMDCs中CDW和SC的调控规律,探讨了TMDCs中CDW和SC之间的关系,展望了未来研究方向和机遇。展开更多
Two-dimensional(2D)transition metal dichalcogenides(TMDs)and their heterostructures(HSs)exhibit unique optical properties and show great promise for developing next-generation optoelectronics.However,the photo-lumines...Two-dimensional(2D)transition metal dichalcogenides(TMDs)and their heterostructures(HSs)exhibit unique optical properties and show great promise for developing next-generation optoelectronics.However,the photo-luminescence(PL)quantum yield of monolayer(1L)TMDs is still quite low at room temperature,which severely lim-its their practical applications.Here we report a PL enhancement effect of 1L WS_(2) at room temperature when con-structing it into 1L-WS_(2)/hBN/1L-MoS_(2) vertical HSs.The PL enhancement factors(EFs)can be up to 4.2.By using transient absorption(TA)spectroscopy,we demonstrate that the PL enhancement effect is due to energy transfer from 1L MoS_(2) to 1L WS_(2).The energy transfer process occurs on a picosecond timescale and lasts more than one hundred picoseconds which indicates a prominent contribution from exciton-exciton annihilation.Furthermore,the PL en-hancement effect of 1L WS_(2) can be observed in 2L-MoS_(2)/hBN/1L-WS_(2) and 3L-MoS_(2)/hBN/1L-WS_(2) HSs.Our study provides a comprehensive understanding of the energy transfer process in the PL enhancement of 2D TMDs and a fea-sible way to optimize the performance of TMD-based optoelectronic devices.展开更多
文摘过渡金属硫族化合物(Transition metal chalcogenides,TMCs)因具有丰富的晶体结构和不寻常的电子特性呈现出有趣的物理现象,引起了人们的持续关注。重点介绍了过渡金属二硫化物(Transition metal dichalcogenides,TMDCs)中电荷密度波(Charge density wave,CDW)和超导电性(Superconductivity,SC)的最新重要发现,系统分析和比较了TMDCs的晶体和能带结构,总结了掺杂和高压对TMDCs中CDW和SC的调控规律,探讨了TMDCs中CDW和SC之间的关系,展望了未来研究方向和机遇。
文摘Two-dimensional(2D)transition metal dichalcogenides(TMDs)and their heterostructures(HSs)exhibit unique optical properties and show great promise for developing next-generation optoelectronics.However,the photo-luminescence(PL)quantum yield of monolayer(1L)TMDs is still quite low at room temperature,which severely lim-its their practical applications.Here we report a PL enhancement effect of 1L WS_(2) at room temperature when con-structing it into 1L-WS_(2)/hBN/1L-MoS_(2) vertical HSs.The PL enhancement factors(EFs)can be up to 4.2.By using transient absorption(TA)spectroscopy,we demonstrate that the PL enhancement effect is due to energy transfer from 1L MoS_(2) to 1L WS_(2).The energy transfer process occurs on a picosecond timescale and lasts more than one hundred picoseconds which indicates a prominent contribution from exciton-exciton annihilation.Furthermore,the PL en-hancement effect of 1L WS_(2) can be observed in 2L-MoS_(2)/hBN/1L-WS_(2) and 3L-MoS_(2)/hBN/1L-WS_(2) HSs.Our study provides a comprehensive understanding of the energy transfer process in the PL enhancement of 2D TMDs and a fea-sible way to optimize the performance of TMD-based optoelectronic devices.
