Spectroscopy and Quantum-State Manipulation of Excited Rb Atoms and Molecules Using Optical Lattices

一般观众摘要：原子光谱学在计量学中很重要，例如时间测量，以及努力了解原子和分子的基本工作原理。例如，Rb原子的5S-5P-5D跃迁被用于实际的蒸汽室原子钟，其波长被长度咨询委员会(CCL)用作实现该仪表的参考之一。在该项目中，测量了可能影响此类设备精度的Rb原子量子态的性质。该项目中进行的激光光谱学研究还旨在更好地了解激光原子陷阱中的高激发态原子(里德堡原子)，探索一种涉及里德堡原子的新型分子，并对里德堡-原子跃迁进行高精度测量，以帮助解决当前基础物理学中的问题(例如，包括质子等物质构件的确切尺寸)。里德堡原子是许多量子设备中的关键组件，这些设备正在进行科学和技术方面的研究，这使得彻底了解它们的物理和可能应用的广度成为一个重要目标。这项研究涉及激光物理、光学、量子力学和量子测量技术等领域的研究生，这些领域在学术界、工业界和政府部门都很受欢迎。技术观众摘要：该项目的工作包括研究1064 nm强激光场下Rb 5D3/2能级的交流偏振率和光致电离截面。激光器是稳定的，并在几个GHz上扫描，同时指的是锁定在原子蒸汽室上的激光器。在1064 nm激光场中，Rb5D3/2能级的交流位移和光致线宽处于相同的数量级，从而可以测量这两个量。在相同的装置中，激光光谱研究被用来探索分子和光学晶格中里德堡原子的物理。里德堡能级可以在GHz深的晶格中严重混合，从而产生新型的势能曲线，并进行了测量。该项目还旨在研究一种介于里德堡原子和阳离子之间的新型分子。在相关工作中，高精度里德堡能级光谱是使用光学晶格调制技术进行的，这是里德堡原子光谱的一种新的亚多普勒光谱方法，它基于束缚电子与场的有质运动相互作用，而不是更常见的电偶极相互作用。全光学制备圆形里德堡原子，这允许最精确的里德堡原子为基础的光谱，使用时间轨道光学晶格。这项工作由一名首席研究员和几名研究生进行，它将为本科生提供机会。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

General audience abstract:Atomic spectroscopy is important in metrology, such as time measurement, and in efforts to learn about the fundamental workings of atoms and molecules. For instance, the 5S-5P-5D transition of the rubidium atom is used in practical vapor-cell atomic clocks, and its wavelength is used by the Consultative Committee for Length (CCL) as one of its references for realizing the meter. In the project, properties of the quantum states of the rubidium atoms are measured that can affect the accuracy of such devices. The laser-spectroscopic investigations conducted in the project also aim at a better understanding of highly excited atoms (Rydberg atoms) in laser atom traps, at the exploration of a new type of molecule that involves Rydberg atoms, and at high-precision measurements of Rydberg-atom transitions that can help address current questions in fundamental physics (including, for instance, what is the exact size of building blocks of matter such as the proton). Rydberg atoms are a critical component in numerous quantum devices that are being worked on in science and technology, making a thorough understanding of their physics and of the breadth of their possible applications an important goal. The research engages graduate students in the fields of laser physics, optics, quantum mechanics and quantum measurement technologies, which are areas that are highly sought-after in academia, industry and government.Technical audience abstract:The project work includes an investigation of the AC polarizability and the photo-ionization cross section of the rubidium 5D3/2 level in a strong 1064-nm laser field. Lasers are stabilized and scanned over several GHz, while being referenced to lasers locked on atomic vapor cells. AC shifts and photo-ionization-induced line broadening of the Rb 5D3/2 level in the 1064-nm laser field are on the same order of magnitude, allowing a measurement of both quantities. In the same setup, laser-spectroscopic studies are conducted to explore the physics of Rydberg atoms in molecules and in optical lattices. Rydberg levels can become heavily mixed in GHz-deep lattices, leading to novel types of potential energy curves, which are measured. The project also aims at research on a new type of molecule between a Rydberg atom and a positive ion. In related work, high-precision Rydberg-level spectroscopy is conducted using an optical-lattice modulation technique, a novel sub-Doppler spectroscopic approach to Rydberg-atom spectroscopy that is based upon the ponderomotive interaction of bound electrons with fields rather than the more common electric-dipole interaction. All-optical preparation of circular Rydberg atoms, which allow for the most precise of Rydberg-atom-based spectroscopies, using a time-orbiting optical lattice is pursued. The work is conducted by a principal investigator and several graduate students, and it will offer opportunities for undergraduate students.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.