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

摘要：原子光谱学在计量学，如时间测量，以及在努力了解原子和分子的基本工作中是重要的。例如，铷原子的5S-5P-5D跃迁用于实际的气相原子钟，其波长被长度咨询委员会（CCL）用作其实现仪表的参考之一。在这个项目中，测量了铷原子的量子态的性质，这可能会影响这种装置的精度。在该项目中进行的激光光谱研究还旨在更好地理解激光原子陷阱中的高激发原子（里德伯原子），探索涉及里德伯原子的新型分子，以及对里德伯原子跃迁的高精度测量，这有助于解决基础物理学中的当前问题（例如，包括质子等物质的确切大小）。里德伯原子是科学和技术中正在研究的许多量子器件的关键组成部分，因此彻底了解它们的物理特性及其可能应用的广度是一个重要目标。该研究招收激光物理、光学、量子力学和量子测量技术领域的研究生，这些领域在学术界、工业界和政府中都是非常受欢迎的。摘要：项目工作包括在1064 nm强激光场中研究铷5D3/2能级的交流极化率和光电离截面。激光是稳定的，扫描在几GHz，而参考激光锁定在原子蒸汽电池。在1064 nm激光场中，Rb 5D3/2能级的交流位移和光电离引起的线展宽在同一个数量级上，从而可以测量这两个量。在相同的设置下，进行了激光光谱研究，以探索分子和光学晶格中的里德伯原子的物理性质。里德伯能级可以在ghz深的晶格中变得严重混合，从而导致测量的新型势能曲线。该项目还旨在研究一种介于里德伯原子和正离子之间的新型分子。在相关工作中，高精度的里德堡能级光谱是使用光学晶格调制技术进行的，这是一种新的亚多普勒光谱方法，用于里德堡-原子光谱，基于束缚电子与场的重动力相互作用，而不是更常见的电-偶极子相互作用。圆形里德伯原子的全光学制备，允许最精确的里德伯原子为基础的光谱，使用时间轨道光学晶格进行。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。

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.