超冷(36D_(5/2)+6S_(1/2))里德伯分子的制备及其电偶极矩的测量  

Preparation of ultra-cold(36D_(5/2)+6S_(1/2))Rydberg molecule and measurement of its permanent electric dipole moment

作　　者：焦月春[1,2] 白景旭 宋蓉 韩小萱 赵建明 Jiao Yue-Chun;Bai Jing-Xu;Song Rong;Han Xiao-Xuan;Zhao Jian-Ming(State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Laser Spectroscopy,Shanxi University,Taiyuan 030006,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China;Department of Physics,Taiyuan Normal University,Jinzhong 030619,China)

机构地区：[1]山西大学激光光谱研究所,量子光学与光量子器件国家重点实验室,太原030006 [2]山西大学,极端光学协同创新中心,太原030006 [3]太原师范学院物理系,晋中030619

出　　处：《物理学报》2023年第3期62-68,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61835007,12120101004,62175136,12104337);长江学者和创新团队发展计划(批准号:RTIRT_17R70);山西省“1331工程”重点学科建设计划;山西省科技合作交流专项(批准号:202104041101015)资助的课题。

摘　　要：里德伯-基态分子由一个里德伯原子和一个基态原子组成,束缚机制是里德伯电子与基态原子的低能电子散射相互作用.理论上,通过低能电子散射Fermi赝势模型,数值计算了铯(36D_(5/2)+6S_(1/2))里德伯-基态分子的绝热势能曲线,提取了里德伯分子的束缚能和平衡核间距等光谱参数.实验上,利用双光子光缔合技术成功制备了散射三重态(^(T)∑,Triplet)和散射单重态-三重态混合(^(S,T)∑,Mixed)形成的里德伯-基态分子,获得了里德伯分子的光缔合光谱,测量的势阱深度与理论计算结果相吻合.另外,以散射三重态为例,分析了里德伯分子的光缔合光谱在外加电场中的展宽现象,获得其平均永久电偶极矩|d|为(12.10±1.65)Debye((4.76±0.65)ea_(0)),与理论计算结果保持一致.该研究为实验上制备D态里德伯-基态分子提供了可行的实验方案,对理解里德伯分子的光谱特性具有重要意义.Ultra-cold long-range Rydberg molecules,consisting of a Rydberg atom and a ground-state atom or another Rydberg atom or ion,have attracted considerable attention due to their exaggerated properties,such as huge size,long chemical bond,large polarization and electric dipole moment,abundant vibrational states and exotic adiabatic potentials.The binding mechanism of Rydberg molecules is a low-energy scattering interaction between the Rydberg electron and the ground state atom for ground-Rydberg molecules or long-range multipole interaction for Rydberg-atom macro dimers and Rydberg-ion molecules,in contrast to covalent bonds,ionic bonds of normal and van der Waals interaction.Owing to its huge size,the dynamic evolution becomes slow compared with normal diatomic molecules and the ultra-long chemical bonds allow being imaged directly by high resolution imaging technology,which makes it convenient to observe the molecular dynamics process c.hemical reaction process in real time.The investigation of Rydberg molecules will be significant for understanding the mechanism of molecular collision and quantum chemical reaction.In this work,we study the ultra-cold Rydberg-ground state molecules theoretically and experimentally.Theoretically,we calculate the adiabatic potential energy curve of cesium(36D_(5/2)+65_(1/2))Rydberg molecule based on the Fermi model of low energy electron scattering by numerically solving the Hamiltonian of Rydberg molecules.And also,we obtain its characteristic parameters,such as the potential depth,binding energy and equilibrium nuclear distance of Rydberg molecule.Experimentally,the Rydberg-ground molecules are investigated by a photo association spectroscopy,where two laser pulses are used to achieve a two-photon transition,and their spectra are obtained by ion detection technology.We successfully observe the Rydbergground state molecular spectra that correspond to a scattering triplet and a scattering single-triplet mixture(^(S,T)∑).The measured binding energy of Rydberg-ground state molecules

关 键 词：超冷里德伯-基态分子 光缔合光谱 绝热势能曲线 电偶极矩 

分 类 号：O561[理学—原子与分子物理]