MRI: Development of a Molecular Beam Instrument for High Resolution Laser Spectroscopy and Quantum Control Studies of Molecular Systems

该项目的目标是开发一种设备，以产生高度可控的分子束，并与精确和高度可控的激光系统相结合，用于光谱学和量子光学研究。这形成了一种仪器，可以研究分子对不同颜色激光的响应，在这种状态下，由于分子的随机热运动而产生的碰撞和其他效应（线展宽）被极大地抑制。具体来说，将研究具有大磁矩的分子（类似于强大但微小的条形磁铁）。这种磁性分子可以通过激光控制，使它们模拟出不寻常的固体材料，这些材料被设计得比天然材料性能更好。此外，该仪器的激光系统提供的高功率将允许开发具有量子计算潜在应用的控制机制。具有部分填充的内壳层的原子表现出较大的磁偶极矩，从而在相互作用中产生极大的各向异性。这种磁性的一些最好的例子是在开放的f壳系镧系元素中发现的，比如镝和铒。由这些原子形成的分子有望具有更大的磁矩，并提供新的偶极性。人们对这类分子的电子结构所知甚少，因为理论从头计算非常具有挑战性。进行这项工作的科学家计划使用该仪器对镧系二聚体的电子结构进行实验性高分辨率光谱研究。这样的光谱研究对量子磁学的发展具有重要意义。对于分子量子控制，仪器的激光系统提供修改（“修饰”）分子能级所需的电磁场（光）。分子态的修饰程度取决于激光辐射的强度。该仪器的激光系统提供的高功率将有助于增强分子系统的量子控制。该仪器的分子束提供了一个无碰撞的环境，具有长相干时间，这在典型的热样品中是不可用的。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。

The goal of this project is to develop an apparatus to produce a highly controlled beam of molecules, integrated with a precise and highly controllable laser system for the purpose of spectroscopic and quantum optics studies. This forms an instrument that will allow the study of the response of molecules to different colors of laser light in a regime where collisions and other effects (line broadening) due to the random thermal motion of the molecules are greatly suppressed. Specifically, molecules with large magnetic moments (analogous to powerful but tiny bar magnets) will be studied. Such magnetic molecules can be controlled by the laser in a way that makes them simulate unusual solid materials that are engineered to outperform naturally occurring materials. In addition, the high power provided by the instrument’s laser system will allow for the development of control mechanisms with potential applications for quantum computing.Atoms with partially filled inner shells exhibit large magnetic dipole moments which give rise to extremely large anisotropy in their interactions. Some of the best examples of such magnetic properties are found in the open f-shell lanthanides like dysprosium and erbium. Molecules formed by such atoms are expected to have even larger magnetic moments and offer novel dipolar properties. Very little is known about the electronic structure of such molecules because theoretical ab initio calculations are very challenging. The scientists carrying out this work plan to use this instrument for an experimental high-resolution spectroscopic study of the electronic structure of the lanthanide dimers. Such a spectroscopic study is important for the developing area of quantum magnetism. For molecular quantum control, the instrument’s laser system provides the electromagnetic field (light) needed to modify (‘dress’) the energy levels of a molecule. The degree of dressing of the molecular states is dependent on the intensity of the laser radiation. The high power provided by the instrument's laser system will facilitate enhanced quantum control of molecular systems. The instrument’s molecular beam provides a collision free environment with long coherence times which is not available in typical thermal samples.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.