RUI: Demonstrating Control Over State-Mixing Interactions in Rydberg Excitation Near Förster Resonance

量子信息领域将给计算、数据安全和我们对基础科学的理解带来革命性的变化。在量子计算机中，单个信息单位或比特存储在单个量子对象中。原子经常被使用，因为它们是电中性的，相互作用非常弱，所以脆弱的量子态可以保持不受干扰。然而，要使用原子进行计算，必须让它们在正确的时间以正确的方式相互作用。解决这个问题的关键是里德堡激发阻塞，当原子冷却到极低温度，最外层的电子被激发到非常大的轨道时，就会产生里德堡激发阻塞。这些高度激发的原子相互作用，这种相互作用可能导致激发被抑制到高位状态。这种对激发的“阻挡”，使人们在追求中性原子量子技术方面取得了许多重要突破。在这个项目中，PI和同事们将研究一个使封锁崩溃的过程：状态混合相互作用。当人们试图将原子激发到相互作用共振附近的特定里德堡态时，原子可能会被高概率混合到其他不想要的状态。这笔拨款将专注于开发控制这些状态混合交互的工具，以便将它们对封锁的影响降至最低。PI和共同PI还将为凯尼恩数学和科学技能中心的首席导师开发一个基于研究的培训计划。培训的重点将是在导师与学生互动时使用元认知，即思考自己的认知过程。PI希望提高学生在STEM课程中的自我效能感，并提高凯尼恩学院STEM学科的持久率。里德伯格激发阻断，即由于强相互作用而抑制激光激发，是使用中性原子实施量子信息协议的关键。Förster共振附近的多粒子Rydberg态之间的耦合产生的态混合相互作用，在其他有利的条件下可能会破坏这种抑制。在最近的工作中，PI和他的学生们表明，导致大的状态混合率的机制敏感地依赖于实验条件。在目前的项目中，他们将利用这种敏感性来开发一个广泛的工具箱，用于控制状态混合交互。该工具箱包括脉冲宽度、拉比频率、原子间距、主量子数和外加电场。他们将把他们的测量结果与不同的理论模型进行比较，这些模型的特征是两个或三个相互作用的粒子。最后，他们将为凯尼恩数学和科学技能中心的首席导师设计一个元认知培训计划，作为鼓励认知高效但正确推理的一种方式。他们将使用经过研究验证的工具来衡量学生自我效能感的变化。自我效能的提高与一系列积极的结果有关，包括坚持STEM。这一奖项反映了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。

The field of quantum information is poised to revolutionize computation, data security, and our understanding of fundamental science. In quantum computers, individual units of information, or bits, are stored in single quantum objects. Atoms are often used because they are electrically neutral and interact very weakly, so fragile quantum states can remain undisturbed. However, to use atoms to do a computation, they must be made to interact at the right time, and in the right way. The key to solving this problem is the Rydberg excitation blockade, which results when atoms are cooled to extremely low temperatures, and the outermost electrons are excited to very large orbits. These highly excited atoms interact, and the interactions can lead to a suppression of excitation into high-lying states. This “blocking” of excitation has led to many important breakthroughs in the pursuit of neutral atom quantum technologies. In this project, the PI and coworkers will study a process that makes the blockade break down: state-mixing interactions. When one tries to excite atoms to a particular Rydberg state near an interaction resonance, the atoms can be mixed into other, unwanted states with high probability. This grant will focus on developing tools to control these state-mixing interactions, so their effect on the blockade can be minimized. The PI and co-PI will also develop a research-based training program for the lead tutors at Kenyon’s Math and Science Skills Center. The training will focus on using metacognition, or thinking about one’s own cognitive processes, when the tutors interact with students. The PIs hope to increase students’ sense of self-efficacy in STEM courses, and enhance persistence rates across STEM disciplines at Kenyon College.The Rydberg excitation blockade, or the suppression of laser excitation due to strong interactions, is the key to using neutral atoms to implement quantum information protocols. State-mixing interactions, which result from couplings among multi-particle Rydberg states near Förster resonance, can compromise this suppression under otherwise favorable conditions. In recent work, the PI and his students showed that the mechanism that causes large rates of state mixing depends sensitively on experimental conditions. In the present project they will exploit this sensitivity to develop a broad toolbox for control over state-mixing interactions. This toolbox includes pulse duration, Rabi frequency, atom separation, principal quantum number, and applied electric field. They will compare their measurements with different theoretical models, characterized by either two or three interacting particles. Finally, they will design a training program in metacognition for lead tutors at Kenyon’s Math and Science Skills Center, as a way to encourage cognitively efficient, but correct reasoning. They will use research-validated instruments to measure changes in students’ self-efficacy. Improved self-efficacy has been linked to a broad range of positive outcomes, including persistence in STEM.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.