Foundations for Trapped Molecular Ion Parity-Violation Studies

该项目开发的技术能够测量镜像对称违逆，使用分子离子长时间保持，几乎静止，并在线性射频陷阱中与环境隔离。需要克服的主要挑战是控制和非破坏性读取单个捕获分子离子的旋转量子态的能力的发展。尽管与原子相比，分子在控制和读出方面需要额外的注意，但其主要优点是，与典型原子的电子能级相比，对偶偶旋转能级本质上能量接近，因此更容易被弱力混合。核自旋相关宇称违反对于理解标准模型的纯强子弱相互作用非常重要，它们为在TeV能量尺度上寻找新物理提供了一种特殊的低能方法。这项工作的动机是核自旋相关宇称违反研究，但改进的精密分子光谱的其他重要应用包括测量电子-质子质量比的时变，研究手性分子结构中的宇称违反，以及发现电子电偶极矩。此外，本文开发的单分子离子光谱学、内外量子态控制和状态读出的组成部分，可能成为分子离子量子信息处理应用和低温化学反应研究的必要元素。本提案中开发的光谱技术有可能影响其他科学领域，如大气和天体物理光谱——在电磁频谱的所谓分子“指纹”区域，人们对开发改进的分子旋转和振动光谱方法和工具非常感兴趣。一个强大的本科和研究生教育和培训计划是由研究维持。目前实验室的学生群体是多样化的，包括代表性不足的少数民族。

This project develops techniques which enable measurement of mirror-symmetry violation, using molecular ions held for long periods of time, nearly at rest, and well isolated from their environment in linear radiofrequency traps. The major challenges to be overcome are development of capabilities to control and non-destructively read out the rotational quantum state of a single trapped molecular ion. Although molecules require extra care in control and readout as compared with atoms, the principle advantage is that opposite-parity rotational levels are intrinsically nearby in energy and thereby more substantially mixed by the weak force than are electronic levels of typical atoms. Nuclear spin-dependent parity violation is important for understanding purely hadronic weak interactions of the Standard Model, and they provide a special low-energy approach for searching for new physics at TeV energy scales. This work is motivated by nuclear spin-dependent parity-violation investigations, but other important applications of improved precision molecular spectroscopy include measurements of time-variation of the electron-proton mass ratio, study of parity violation in the structure of chiral molecules, and discovery of an electron electric dipole moment. Furthermore, the ingredients for single molecular ion spectroscopy, internal and external quantum state control and state readout developed here, could be essential elements for molecular-ion quantum information processing applications and for studies of low-temperature chemical reactions. The spectroscopic techniques being developed in this proposal have potential to impact other areas of science as diverse as atmospheric and astrophysical spectroscopy -- where there is great interest in developing improved methods and tools for molecular rotational and vibrational spectroscopy in the so-called molecular "fingerprint" region of the electromagnetic spectrum. A strong program of undergraduate and graduate education and training is maintained by the research. The current group of students in the lab is diverse and includes underrepresented minorities.