CAREER: Interactions in Cold Molecular Systems

该职业奖支持一项实验研究计划，研究在接近绝对零度的未探索温度范围内的冷和超冷分子碰撞和化学反应。极性分子之间的相互作用与冷原子之间的相互作用截然不同。分子系统中的长程偶极-偶极相互作用不仅在大小上是各向异性的，而且在符号上也是各向异性的。这些大的各向异性相互作用创造了新的动力学和手柄来控制极性分子系统中的碰撞。冷分子将通过斯塔克减速产生，斯塔克减速使用不均匀的电场来减缓分子的静止。产生的分子将被电场和磁场捕获，导致长的相互作用时间，从而精确测量碰撞。一旦冷的致密样品被创建，将在毫开尔文温度下研究铷原子的化学反应和碰撞。到目前为止，化学家还无法研究低于10 K的反应。了解低温反应对于模拟包括星际云化学在内的几个相关化学系统至关重要。 这项工作的更广泛的影响包括一个综合计划，以提高学生的实验科学学习。几个层次的学生将在这个程序中解决。第一组将是高水平的本科物理专业。 本科生往往没有接触到专业研究的过程。大多数高级实验室课程本质上是食谱，未能教会学生独立研究的必要技能。一个系统的，以评估为基础的方法将采取改变高层次的实验室课程的结构和内容，以解决本科教育的这一不足。 除了重组高级实验室课程，一个研讨会会议题为？从灯泡到激光？将发展向中学女生介绍实验科学的课程。

This CAREER award supports an experimental research program investigating cold and ultracold molecular collisions and chemical reactions in an unexplored temperature regime close to absolute zero. Interactions between polar molecules are critically different from those between cold atoms. The long-range dipole-dipole interactions present in molecular systems are anisotropic not only in magnitude, but also in sign. These large anisotropic interactions create new dynamics and handles to control collisions in polar molecule systems. Cold molecules will be produced by Stark deceleration, which uses inhomogeneous electric fields to slow the molecules to rest. The resulting molecules will be trapped using electric and magnetic fields leading to long interactions times and thus precise measurements of the collisions. Once the cold dense samples are created, chemical reactions and collisions with rubidium atoms will be studied at milliKelvin temperatures. Until now, chemists have been not been able to study reactions below 10K. Understanding lower temperature reactions is critical to modeling several relevant chemical systems including interstellar cloud chemistry. The broader impacts of this work include an integrated plan for improving student learning of experimental science. Several levels of students will be addressed in this program. The first group will be upper-level undergraduate physics majors. Undergraduate students often are not exposed to the process of professional research. Most senior lab courses are cookbook in nature and fail to teach students the necessary skills for independent research. A systematic, evaluation-based approach will be taken to change the senior-level lab course in both structure and content to address this deficiency in undergraduate education. In addition to restructuring the senior lab course, a workshop session titled ?From light bulbs to lasers? will be developed to introduce middle-school-aged girls to experimental science.