Investigation of Clock Transitions in Single and Coupled Molecular Spin Qubits

在化学系化学结构、动力学和机理B(CSDM-B)计划的支持下，佛罗里达州立大学化学和生物化学系的Mykhailo Shatruk教授和物理系和国家高磁场实验室的Stephen Hill教授正在研究可以用作量子信息处理量子比特的磁性分子的方法。该项目的重点是具有量子时钟跃迁的稀土络合物，这可以保护分子量子比特免受外部磁噪声的影响，并延长量子纠缠的持续时间-这是实现量子技术的关键因素。该项目将培训无机化学、量子物理和材料科学方面的初级科学家，从而为未来量子劳动力的教育做出贡献。该项目团队计划组织一次全国性的本科暑期学校，对学生进行磁性材料方面的教育。推广活动还将涉及高中生和普通公众，旨在扩大在物理科学中代表性不足的群体的成员的参与。顺磁分子络合物是开发电子自旋量子比特的很有前途的平台，因为它们的合成具有很高的可调性，能够实现目标磁参数。这个项目将涉及到将稀土络合物作为潜在的电子自旋量子比特的研究，重点是由于晶场分裂产生的基态双重态的混合而打开量子隧道禁带而出现的量子时钟跃迁(QCT)。在QCT中，电子自旋对周围的自旋池变得不敏感，导致量子相干时间急剧增加，从而保护纠缠态不受磁场噪声的影响。该项目的第一阶段涉及对单核复合体的研究，以确定最有希望显示隧道间隙和相干时间的期望值的QCT系统。第二阶段将致力于通过光或氧化还原可切换链接器连接这些量子比特，使量子门操作成为可能。先进的表征方法，包括一套电子顺磁共振技术、远红外磁谱、非弹性中子散射和理论建模，将用于研究分子量子比特并指导进一步的合成工作。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。

With support from the Chemical Structure, Dynamics & Mechanisms-B (CSDM-B) Program of the Chemistry Division, Professors Mykhailo Shatruk of the Department of Chemistry and Biochemistry and Stephen Hill of the Department of Physics and National High Magnetic Field Laboratory at Florida State University are investigating approaches to magnetic molecules that can serve as qubits for quantum information processing. The project focuses on lanthanide complexes with quantum clock transitions, which can provide protection of the molecular qubits against external magnetic noise and prolong the duration of quantum entanglement – a crucial factor for the implementation of quantum technologies. The project will train junior scientists at the nexus of inorganic chemistry, quantum physics, and materials science, thus contributing to the education of the future quantum workforce. The project team plans to organize a nationwide undergraduate summer school to educate students about magnetic materials. Outreach activities will also involve high-school students and the general public, and are aimed at broadening participation by members of groups underrepresented in physical sciences.Paramagnetic molecular complexes are promising platforms for the development of electron spin qubits, due to the high tunability of their synthesis that allows realization of targeted magnetic parameters. This project will involve the examination of lanthanide complexes as potential electron spin qubits, with a focus on quantum clock transitions (QCTs) that emerge from the opening of quantum tunneling gaps due to mixing of ground doublet states generated by crystal field splitting. At the QCT, electron spin becomes insensitive to the surrounding spin bath, leading to a dramatic increase in the quantum coherence time, thus allowing protection of the entangled state from the magnetic noise. The first stage of this project involves the investigation of mononuclear complexes to identify the most promising QCT systems that demonstrate the desired values of tunneling gap and coherence time. The second stage will be devoted to connecting such qubits through a photo- or redox-switchable linkers, to make possible quantum gate operations. Advanced characterization methods, including a suite of electron paramagnetic resonance techniques, far-infrared magnetic spectroscopy, inelastic neutron scattering, and theoretical modeling will be used to investigate the molecular qubits and guide further synthetic efforts.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.