Molecular Quantum Control and Spectroscopy Using Light-Dressed States

使用轻装态的分子量子控制和光谱学

• 批准号: 2207665
• 负责人: A. Marjatta Lyyra
• 金额: $ 55.77万
• 依托单位: Temple University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2207665&HistoricalAwards=false
• 关键词: Molecular; Quantum; Control; Spectroscopy; Using

The internal degrees of freedom, such as vibrations and rotations, of molecules and the variety of interactions between their quantum states give rise to a rich energy level structure. Diatomic molecules (those with two atoms) are ideal for experiments which are not possible with atoms but avoid the overwhelming complexity of polyatomic molecules. This project utilizes the interaction of laser radiation with diatomic molecules to study the strength of transitions between energy states, investigate the electronic structure of diatomic molecules composed of atoms of dysprosium or its relatives, and create molecular orientation. The two main ways by which chemical bonds are formed between atoms involve sharing of valence electrons (covalent) or a transfer of valence electrons from one atom to another (ionic). In many instances the nature of the chemical bond is a mixture of ionic and covalent character. Furthermore, theoretical predictions indicate that the character of a chemical bond can gradually change as a function of various parameters including the internuclear distance. The planned transition dipole moment measurements probe the strength of the interaction of an atom or a molecule with light. Such measurements provide a sensitive way to explore the changes in molecular electronic structure between covalent and ionic bonding. The research team will also study diatomic molecules formed from atoms with large magnetic moments such as dysprosium and erbium with unconventional magnetic properties and strong anisotropic interactions. The electronic structure of such dimer molecules is completely unknown experimentally. These studies will provide the missing critical data needed for the understanding of highly anisotropic interactions at short internuclear distance range and the realization of quantum gases of molecules with large magnetic moments. The control of molecular orientation experiments of the project will be of importance for the study of reactions of molecules with other molecules and atoms. The principal investigators will continue to strive engaging a diverse set of Physics students in research both at the graduate and undergraduate levels. The Optics and the Atomic, Molecular and Optical Physics courses taught by the principal investigators also serve interested chemistry and biophysics students.This project involves a unique combination of multiple resonance high resolution spectroscopy and quantum optics techniques of dressed molecular quantum states with light for the purposes of quantum control. The SolsTiS laser system funded by the NSF MRI grant 2018443 provides a critical enhancement of laser power, tuning range, and frequency stability for the coupling laser in the proposed experiments. The dressed-states approach with an enhanced Rabi frequency will make it possible to control molecular alignment and orientation to study the effects of collisions on the rotational angular momentum of diatomic molecules. The ability to manipulate the rotational angular momentum of molecules makes it possible to obtain molecular frame information as well as allow control of physical and chemical processes whose rates are dependent on the orientation of the molecular axis. In addition, it will be possible to probe the transition dipole moment behavior in regions of avoided crossings between covalent diabatic potential energy functions and the ion-pair potential. The interaction of these potentials leads to large changes in the transition dipole moment and interesting long range potential energy wells with dense energy level structure with unusual radiative properties. The planned high resolution spectroscopic investigation of the lanthanide dimers will extend the atomic systems quantum magnetism studies to molecular systems with even larger magnetic moments than the atoms. These experiments will provide critical data for recent theoretical ab initio studies of the electronic structure of these important magnetic molecules.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

分子的内部自由度，如振动和旋转，以及它们的量子态之间的各种相互作用，产生了丰富的能级结构。双原子分子（具有两个原子的分子）是理想的实验，这些实验不可能用原子进行，但避免了多原子分子的压倒性复杂性。本项目利用激光辐射与双原子分子的相互作用，研究能量态之间跃迁的强度，研究由镝或其近亲原子组成的双原子分子的电子结构，并创建分子取向。原子之间形成化学键的两种主要方式包括共用价电子（共价键）或价电子从一个原子转移到另一个原子（离子键）。在许多情况下，化学键的性质是离子和共价键的混合物。此外，理论预测表明，化学键的性质可以随着包括核间距在内的各种参数的变化而逐渐改变。计划中的跃迁偶极矩测量探测原子或分子与光相互作用的强度。这种测量为探索共价键和离子键之间分子电子结构的变化提供了一种灵敏的方法。研究小组还将研究由具有大磁矩的原子形成的双原子分子，如镝和铒，它们具有非常规的磁性和强各向异性相互作用。这种二聚体分子的电子结构在实验上是完全未知的。这些研究将为理解短核间高度各向异性相互作用和实现具有大磁矩的分子量子气体提供缺失的关键数据。本课题分子取向实验的控制对研究分子与其他分子和原子的反应具有重要意义。主要研究人员将继续努力吸引各种各样的物理系学生参与研究生和本科生的研究。由主要研究人员教授的光学和原子，分子和光学物理课程也为感兴趣的化学和生物物理学学生提供服务。本项目将多共振高分辨率光谱技术与光修饰分子量子态的量子光学技术独特地结合起来，用于量子控制。由NSF MRI拨款2018443资助的SolsTiS激光系统在拟议的实验中为耦合激光器提供了激光功率，调谐范围和频率稳定性的关键增强。提高拉比频率的衣态方法可以控制分子的排列和取向，从而研究碰撞对双原子分子旋转角动量的影响。操纵分子旋转角动量的能力使得获得分子框架信息成为可能，也使得控制速率依赖于分子轴方向的物理和化学过程成为可能。此外，还可以探测共价非绝热势能函数和离子对势之间避免交叉区域的跃迁偶极矩行为。这些势的相互作用导致了跃迁偶极矩的巨大变化和具有致密能级结构和不寻常辐射特性的有趣的远程势阱。计划中的镧系二聚体的高分辨率光谱研究将把原子系统的量子磁学研究扩展到具有比原子更大磁矩的分子系统。这些实验将为最近对这些重要磁性分子的电子结构进行从头算理论研究提供关键数据。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。