QLC: EAGER: Toward Magnetic Selectivity with Molecular Clock Qubits

本课题由化学系化学结构与动力学机制B项目资助，约瑟夫·M科罗拉多州立大学化学系的Zadrozny正在开发用于检测生理磁现象的新型金属络合物。这些复合物被设计为量子计算机的基于自旋的量子比特（qubit）的分子模拟物。分子量子比特对它们的局部环境极其敏感，这种敏感性在量子计算应用中将被抑制。这项工作将从一个不同的方向出发，提出一个基本的问题：分子量子比特的固有灵敏度能否被用来创造新的生物成像传感器？对于这样的应用，期望将量子位的极端灵敏度集中于特定的环境因素。该计划将朝着选择性敏感性的愿景迈出第一步。作为该项目的一部分，外联活动包括制作一个学习工具包，向K-12级的学生讲授基本磁现象。一种新生类型的分子量子比特是所谓的时钟量子比特，其具有长的自旋-晶格和自旋-自旋弛豫时间，这是由于对磁现象的强烈不敏感性。这种不敏感性与传统的分子量子比特形成了鲜明的对比，后者具有受局部磁性强烈影响的弛豫时间。这两类量子比特的相对灵敏度表明了对附近磁性的敏感性的固有可调性，这可能使基于弛豫时间的传感探针能够仅针对特定类别的环境自旋，例如发生在不同类型的生物分子中的自旋。在这项工作中，基于V（IV）分子量子比特的模型系统将探索时钟量子比特行为的核心问题：（1）这些系统如何与不同类别的环境核自旋相互作用？(2)这些时钟量子比特如何与不同类别的邻近电子自旋相互作用？最后，（3）这种相互作用对于某些自旋类别是否比其他自旋类别更有利，支配这种有利的因素是什么？这些基本问题中的每一个都是对特定类型的自旋生物相关分子的靶向灵敏度的最终发展的基础。该奖项反映了NSF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。

In this project, funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor Joseph M. Zadrozny of the Department of Chemistry at Colorado State University is developing new classes of metal complexes for the detection of physiological magnetic phenomena. These complexes are designed as molecular analogues to spin-based quantum bits (qubits) of a quantum computer. Molecular qubits are extremely sensitive to their local environment, a sensitivity that is to be suppressed for quantum computing applications. The proposed work will embark in a different direction by asking the fundamental question: Can the inherent sensitivity of molecular qubits be embraced to create new bioimaging sensors? Toward such application, it is desirable to focus the extreme sensitivity of a qubit toward specific environmental factors. This program will take the first fundamental steps toward that vision of selective sensitivity. Outreach activities as part of this project include the creation of a learning kit to instruct students at the K-12 level on fundamental magnetic phenomena. A nascent type of molecular qubits are the so-called clock qubits, which possess long spin-lattice and spin-spin relaxation times that result from a strong insensitivity to magnetic phenomena. This insensitivity stands as a stark counterpoint to conventional molecular qubits, which possess relaxation times that are strongly affected by local magnetism. The relative sensitivity of the two classes of qubits indicates an inherent tunability of susceptibility to nearby magnetism, potentially enabling relaxation-time-based sensing probes to be targeted toward only specific classes of environmental spins, e.g. those that occur in different types of biomolecules. In this work, a model system based on a V(IV) molecule qubit will explore fundamental questions at the heart of clock qubit behavior: (1) How do these systems interact with different classes of environmental nuclear spins? (2) How do these clock qubits interact with different classes of proximate electronic spins? Finally, (3) Is this interaction at all favored for certain classes of spins over others, and what are the factors that govern that favor? Each of these fundamental questions underlies the eventual development of targeted sensitivity toward specific types of spin-bearing biologically relevant molecules.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.