Exciton physics in atomically thin transition-metal dichalcogenides(TMDCs)holds paramount importance for fundamental physics research and prospective applications.However,the experimental exploration of exciton physic...Exciton physics in atomically thin transition-metal dichalcogenides(TMDCs)holds paramount importance for fundamental physics research and prospective applications.However,the experimental exploration of exciton physics,including excitonic coherence dynamics,exciton many-body interactions,and their optical properties,faces challenges stemming from factors such as spatial heterogeneity and intricate many-body effects.In this perspective,we elaborate upon how optical two-dimensional coherent spectroscopy(2DCS)emerges as an effective tool to tackle the challenges,and outline potential directions for gaining deeper insights into exciton physics in forthcoming experiments with the advancements in 2DCS techniques and new materials.展开更多
Strong-field photoelectron holography is promising for the study of electron dynamics and structure in atoms and molecules,with superior spatiotemporal resolution compared to conventional electron and X-ray diffractom...Strong-field photoelectron holography is promising for the study of electron dynamics and structure in atoms and molecules,with superior spatiotemporal resolution compared to conventional electron and X-ray diffractometry.However,the application of strong-field photoelectron holography has been hindered by inter-cycle interference from multicycle fields.Here,we address this challenge by employing a near-single-cycle field to suppress the inter-cycle interference.We observed and separated two distinct holographic patterns for the first time.Our measurements allow us not only to identify the Gouy phase effect on electron wavepackets and holographic patterns but also to correctly extract the internuclear separation of the target molecule from the holographic pattern.Our work leads to a leap jump from theory to application in the field of strong-field photoelectron holography-based ultrafast imaging of molecular structures.展开更多
Coulomb potential may induce a significant angular offset to the two-dimensional photoelectron momentum distributions for atoms subject to strong elliptically polarized laser fields.In the attoclock experiment,this of...Coulomb potential may induce a significant angular offset to the two-dimensional photoelectron momentum distributions for atoms subject to strong elliptically polarized laser fields.In the attoclock experiment,this offset usually cannot be easily disentangled from the contribution of tunneling delay and poses a main obstacle to the precise measurement of tunneling delay.Based on semiclassical calculations,here,we propose a method to extract the equivalent temporal offset induced solely by Coulomb potential(TOCP)in an attoclock experiment.Our calculations indicate that,at constant laser intensity,the TOCP shows distinctive wavelength dependence laws for different model atoms,and the ratio of the target atom’s TOCP to that of H becomes insensitive to wavelength and linearly proportional to(2Ip)?3/2,where Ip is the ionization potential of the target atom.This wavelength and Ip dependence of TOCP can be further applied to extract the Coulomb potential influence.Our work paves the way for an accurate measurement of the tunneling delay in the tunneling ionization of atoms subject to intense elliptically polarized laser fields.展开更多
基金S.Y.and X.L.acknowledge the support from the National Natural Science Foundation of China(Grant Nos.12121004 and 12004391)the China Postdoctoral Science Foundation(Grants Nos.2020T130682 and 2019M662752)+6 种基金the Science and Technology Department of Hubei Province(Grant No.2020CFA029)the Knowledge Innovation Program of Wuhan-Shuguang Project.T.J.acknowledges the support from the National Natural Science Foundation of China(Grant Nos.62175188 and 62005198)the Shanghai Science and Technology Innovation Action Plan Project(Grant No.23ZR1465800)X.C.acknowledges support from the National Natural Science Foundation of China(Grant Nos.61925504,62020106009,and 6201101335)Science and Technology Commission of Shanghai Municipality(Grant Nos.17JC1400800,20JC1414600,and 21JC1406100)the Special Development Funds for Major Projects of Shanghai Zhangjiang National Independent Innovation Demonstration Zone(Grant No.ZJ2021-ZD-008)D.H.acknowledges the support from the Fundamental Research Funds for the Central Universities.
文摘Exciton physics in atomically thin transition-metal dichalcogenides(TMDCs)holds paramount importance for fundamental physics research and prospective applications.However,the experimental exploration of exciton physics,including excitonic coherence dynamics,exciton many-body interactions,and their optical properties,faces challenges stemming from factors such as spatial heterogeneity and intricate many-body effects.In this perspective,we elaborate upon how optical two-dimensional coherent spectroscopy(2DCS)emerges as an effective tool to tackle the challenges,and outline potential directions for gaining deeper insights into exciton physics in forthcoming experiments with the advancements in 2DCS techniques and new materials.
基金supported in part by the National Research Foundation of Korea(NRF)Grants(Grant Nos.2022M3H4A1A04074153,2020R1A2C2103181,and RS-2022-00154676)funded by the Ministry of Science,ICTby Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0008763,HRD Program for Industrial Innovation)+1 种基金The National Natural Science Foundation of China(Nos.12121004,12274420,and 11922413)CAS Project for Young Scientists in Basic Research,Grant No.YSBR-055.
文摘Strong-field photoelectron holography is promising for the study of electron dynamics and structure in atoms and molecules,with superior spatiotemporal resolution compared to conventional electron and X-ray diffractometry.However,the application of strong-field photoelectron holography has been hindered by inter-cycle interference from multicycle fields.Here,we address this challenge by employing a near-single-cycle field to suppress the inter-cycle interference.We observed and separated two distinct holographic patterns for the first time.Our measurements allow us not only to identify the Gouy phase effect on electron wavepackets and holographic patterns but also to correctly extract the internuclear separation of the target molecule from the holographic pattern.Our work leads to a leap jump from theory to application in the field of strong-field photoelectron holography-based ultrafast imaging of molecular structures.
基金supported by the National Key Research and Development Program of China(Nos.2019YFA0307702,2019YFA0307704,and 2016YFA0401100)the National Natural Science Foundation of China(Nos.11974383,11834015,11847243,11804374,11874392,11774387,11527807,and 11425414)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB21010400)。
文摘Coulomb potential may induce a significant angular offset to the two-dimensional photoelectron momentum distributions for atoms subject to strong elliptically polarized laser fields.In the attoclock experiment,this offset usually cannot be easily disentangled from the contribution of tunneling delay and poses a main obstacle to the precise measurement of tunneling delay.Based on semiclassical calculations,here,we propose a method to extract the equivalent temporal offset induced solely by Coulomb potential(TOCP)in an attoclock experiment.Our calculations indicate that,at constant laser intensity,the TOCP shows distinctive wavelength dependence laws for different model atoms,and the ratio of the target atom’s TOCP to that of H becomes insensitive to wavelength and linearly proportional to(2Ip)?3/2,where Ip is the ionization potential of the target atom.This wavelength and Ip dependence of TOCP can be further applied to extract the Coulomb potential influence.Our work paves the way for an accurate measurement of the tunneling delay in the tunneling ionization of atoms subject to intense elliptically polarized laser fields.
