Molecular qubits that respond to light Spins in solid-state systems such as quantum dots and defect centers in diamond can easily be controlled by light for use in quantum information processing. More challenging is tuning their properties and making large arrays, something that can be done more easily with spins in molecules. Bayliss et al. combined the advantages of the two approaches by designing and characterizing three related molecular species that are optically addressable. The molecules consist of a central chromium ion surrounded by organic ligands, and their spin and optical properties can be tailored by simply changing the positions of methyl groups on the ligands. Science, this issue p. 1309 Three organometallic molecules that can be controlled by light are designed and characterized. Spin-bearing molecules are promising building blocks for quantum technologies as they can be chemically tuned, assembled into scalable arrays, and readily incorporated into diverse device architectures. In molecular systems, optically addressing ground-state spins would enable a wide range of applications in quantum information science, as has been demonstrated for solid-state defects. However, this important functionality has remained elusive for molecules. Here, we demonstrate such optical addressability in a series of synthesized organometallic, chromium(IV) molecules. These compounds display a ground-state spin that can be initialized and read out using light and coherently manipulated with microwaves. In addition, through atomistic modification of the molecular structure, we vary the spin and optical properties of these compounds, indicating promise for designer quantum systems synthesized from the bottom-up.

中文翻译：

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用于量子信息处理的光学可寻址分子自旋

响应固态系统中的光自旋的分子量子位，例如金刚石中的量子点和缺陷中心，可以很容易地由光控制，用于量子信息处理。更具挑战性的是调整它们的特性并制作大型阵列，这可以通过分子中的自旋更容易地完成。贝利斯等人。通过设计和表征三种可光学寻址的相关分子种类，结合了两种方法的优点。这些分子由一个被有机配体包围的中心铬离子组成，它们的自旋和光学特性可以通过简单地改变配体上甲基的位置来定制。科学，这个问题 p。1309 设计并表征了三种可受光控制的有机金属分子。自旋分子是量子技术的有前途的构建模块，因为它们可以进行化学调谐，组装成可扩展的阵列，并且很容易整合到不同的设备架构中。在分子系统中，光学寻址基态自旋将在量子信息科学中实现广泛的应用，正如固态缺陷所证明的那样。然而，这种重要的功能对于分子来说仍然难以捉摸。在这里，我们在一系列合成的有机金属铬 (IV) 分子中证明了这种光学寻址能力。这些化合物显示出基态自旋，可以使用光进行初始化和读取，并使用微波进行相干操纵。此外，通过分子结构的原子修饰，我们改变了这些化合物的自旋和光学特性，