O433.54 2002053307激光感生碰撞能量转移实验=Experiments of laserinduced collision energy transfer[刊,中]/郑瑞华,陈德应,吕志伟,赵晓彦,马祖光(哈尔滨工业大学光电子研究所.黑龙江,哈尔滨(150001))//光学学报.—2001,21(8)...O433.54 2002053307激光感生碰撞能量转移实验=Experiments of laserinduced collision energy transfer[刊,中]/郑瑞华,陈德应,吕志伟,赵晓彦,马祖光(哈尔滨工业大学光电子研究所.黑龙江,哈尔滨(150001))//光学学报.—2001,21(8).—961-964观察到Eu(6s6p)<sup>8</sup>P<sub>9/2</sub>至Sr(5s10s)S<sub>0</sub>。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
In this work,we employ electronic structure calculations and nonadiabatic dynamics simulations based on many-body Green function and BetheSalpeter equation(GW/BSE)methods to study excited-state properties of a zinc ph...In this work,we employ electronic structure calculations and nonadiabatic dynamics simulations based on many-body Green function and BetheSalpeter equation(GW/BSE)methods to study excited-state properties of a zinc phthalocyanine-fullerene(ZnPcC_(60))dyad with 6-6 and 5-6 configurations.In the former,the initially populated locally excited(LE)state of ZnPc is the lowest S1 state and thus,its subsequent charge separation is relatively slow.In contrast,in the latter,the S1 state is the LE state of C_(60)while the LE state of ZnPc is much higher in energy.There also exist several charge-transfer(CT)states between the LE states of ZnPc and C_(60).Thus,one can see apparent charge separation dynamics during excited-state relaxation dynamics from the LE state of ZnPc to that of C_(60).These points are verified in dynamics simulations.In the first 200 fs,there is a rapid excitation energy transfer from ZnPc to C_(60),followed by an ultrafast charge separation to form a CT intermediate state.This process is mainly driven by hole transfer from C_(60)to ZnPc.The present work demonstrates that different bonding patterns(i.e.5-6 and 6-6)of the C−N linker can be used to tune excited-state properties and thereto optoelectronic properties of covalently bonded ZnPc-C_(60)dyads.Methodologically,it is proven that combined GW/BSE nonadiabatic dynamics method is a practical and reliable tool for exploring photoinduced dynamics of nonperiodic dyads,organometallic molecules,quantum dots,nanoclusters,etc.展开更多
Based on the four-state model of laser-induced collisional energy transfer,the cross section of the collisional energy transfer in the Sr-Ca system is obtained.Various factors,including field intensity,relative speed,...Based on the four-state model of laser-induced collisional energy transfer,the cross section of the collisional energy transfer in the Sr-Ca system is obtained.Various factors,including field intensity,relative speed,and temperature,which influence the collisional cross section,are discussed for illustrating the features of the Sr-Ca laser-induced collisional energy transfer(LICET) process.The calculated results show that the LICET spectral profiles obviously become narrower when the laser field intensity increases.The collision cross section rises with laser intensity and tends to saturate.In the vicinity of the spectral profile center,the cross section at fixed laser detuning becomes smaller as the relative speed and system temperature increase.The results indicate that the intermediate states strongly affect the spectral profile of LICET.展开更多
文摘O433.54 2002053307激光感生碰撞能量转移实验=Experiments of laserinduced collision energy transfer[刊,中]/郑瑞华,陈德应,吕志伟,赵晓彦,马祖光(哈尔滨工业大学光电子研究所.黑龙江,哈尔滨(150001))//光学学报.—2001,21(8).—961-964观察到Eu(6s6p)<sup>8</sup>P<sub>9/2</sub>至Sr(5s10s)S<sub>0</sub>。
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.
文摘目的确认TrkA与snapin蛋白间的直接相互作用。方法采用DNA重组技术,构建增强型荧光蛋白表达载体pECFP-TrkAICD(TrkA膜内区)和pEYFP-snapin,共转染HEK 293T细胞后以激光扫描共聚焦显微镜观察并进行荧光共振能量转移(fluorescence resonance energy transfer,FRET)分析。结果成功构建了snapin和TrkA的重组质粒,共转染细胞后激光扫描共聚焦显微镜分析表明两种蛋白分布在细胞质同一层面,荧光共振能量转移(FRET)分析表明能量转移效率>5%,与对照相比有显著区别(P<0.05)。结论激光扫描共聚焦及FRET实验结果都证明了TrkA膜内区与snapin两个蛋白之间存在着直接的相互作用。
基金support from the National Natural Science Foundation of China(No.21688102,No.21590801,and No.21520102005)support from Sichuan Science and Technology Program Grant(2020YJ0161)。
文摘In this work,we employ electronic structure calculations and nonadiabatic dynamics simulations based on many-body Green function and BetheSalpeter equation(GW/BSE)methods to study excited-state properties of a zinc phthalocyanine-fullerene(ZnPcC_(60))dyad with 6-6 and 5-6 configurations.In the former,the initially populated locally excited(LE)state of ZnPc is the lowest S1 state and thus,its subsequent charge separation is relatively slow.In contrast,in the latter,the S1 state is the LE state of C_(60)while the LE state of ZnPc is much higher in energy.There also exist several charge-transfer(CT)states between the LE states of ZnPc and C_(60).Thus,one can see apparent charge separation dynamics during excited-state relaxation dynamics from the LE state of ZnPc to that of C_(60).These points are verified in dynamics simulations.In the first 200 fs,there is a rapid excitation energy transfer from ZnPc to C_(60),followed by an ultrafast charge separation to form a CT intermediate state.This process is mainly driven by hole transfer from C_(60)to ZnPc.The present work demonstrates that different bonding patterns(i.e.5-6 and 6-6)of the C−N linker can be used to tune excited-state properties and thereto optoelectronic properties of covalently bonded ZnPc-C_(60)dyads.Methodologically,it is proven that combined GW/BSE nonadiabatic dynamics method is a practical and reliable tool for exploring photoinduced dynamics of nonperiodic dyads,organometallic molecules,quantum dots,nanoclusters,etc.
文摘Based on the four-state model of laser-induced collisional energy transfer,the cross section of the collisional energy transfer in the Sr-Ca system is obtained.Various factors,including field intensity,relative speed,and temperature,which influence the collisional cross section,are discussed for illustrating the features of the Sr-Ca laser-induced collisional energy transfer(LICET) process.The calculated results show that the LICET spectral profiles obviously become narrower when the laser field intensity increases.The collision cross section rises with laser intensity and tends to saturate.In the vicinity of the spectral profile center,the cross section at fixed laser detuning becomes smaller as the relative speed and system temperature increase.The results indicate that the intermediate states strongly affect the spectral profile of LICET.