Quantum Logic with Prototype Molecular Spin-Qubits

这个项目将集中于合成一个新的分子量子位库，并通过配位化学将它们连接起来，组装成两个和三个量子比特门的原型。自旋量子比特表现为与抗磁性过渡金属的配位络合物，该配位金属由氧化还原活性的二硫烯配体结合，该配体可以很容易地被化学或电化学氧化以产生未配对的自旋。氧化还原惰性四膦配体将连接两个金属二硫烯单元，它们随后的氧化产生两个弱耦合自旋-两个退出系统。弱耦合是必不可少的，这样分子才能被物理寻址以访问三重态。该项目首先制备了一系列具有不同金属离子、二硫杂环烯取代基和双膦桥联结构的双金属络合物，以调节电子耦合。先进的光谱表征和理论研究将确定两量子比特选通的最佳组成。合成模体将被扩展为包括可切换的功能，其中可以在有限的时间段内产生未配对的自旋，以创建各种自旋状态。开关将通过外部刺激，使用光、磁场或电进行访问。对这些典型的两量子比特门和三量子比特门的测试将有助于更深入地理解量子计算的基本要求。

This project will concentrate on synthesising a library of new molecular qubits and linking these through coordination chemistry to assemble prototype two- and three-qubit gates. The spin-qubit manifests as a coordination complex with a diamagnetic transition metal bound by a redox-active dithiolene ligand which can be readily oxidised chemically or electrochemically to generate unpaired spins. A redox-inert tetraphosphine ligand will bridge two metallodithiolene units, and their subsequent oxidation generates two weakly coupled spins - a two-quit system. The weak coupling is essential so that the molecule can be physically addressed to access the triplet state. The project begins with the preparation of a series of dimetallic complexes with different the metal ions, dithiolene substituents and diphosphine bridge structure to modulate the electronic coupling. Advanced spectroscopic characterisation and theoretical studies will define the optimal composition for two-qubit gating. The synthetic motif will be extended to incorporate switchable functionalities where unpaired spins can be generated for a finite period of time to create a variety of spin states. The switch will be accessed via an external stimulus, using light, magnetic fields, or electricity. Testing of these prototypical two- and three-qubit gates will facilitate a deeper understanding of the fundamental requirements for quantum computing.