Precise and Robust Quantum Gates for Spin Qubits in Diamond-NV Centers

金刚石中与氮空位中心相关的电子和核自旋已成为最有前途的固态量子比特之一。使它们如此吸引人的特性包括有限的希尔伯特空间，出色的可控性和长相干时间，所有这些都导致实现高精度量子算法的可能性。此外，相对容易的初始化和读出单个量子位，以及室温操作的可能性，使得实验实现的障碍比其他固态系统更低。该项目的目标是实现这一潜力，即在NV中心的基础上实现量子寄存器，并在这些系统中实现演示型量子任务的最佳实现。我们的主要重点将是优化精度（保真度）和栅极操作的稳健性。这包括保护量子寄存器免受环境噪声的影响，以及对实验缺陷不敏感的门的设计和实现，例如控制场幅度的偏差。在过去，我们在这个目标上取得了很好的进展，主要是在单量子比特上。在目前的项目中，我们将专注于将这些结果扩展到多量子位系统，特别是由电子和核自旋组成的混合系统。

The electronic and nuclear spins associated with the nitrogen-vacancy center in diamond have become some of the most promising solid-state qubits. The properties that make them so attractive include the limited Hilbert space, excellent controllability, and long coherence times, all leading to the possibility of implementing quantum algorithms with high precision. In addition, the relatively easy initialization and readout of individual qubits and the possibility of room-temperature operation lead to lower hurdles for experimental implementations than in other solid-state systems. The goal of this project is the realization of this potential, i.e. the implementation of quantum registers on the basis of NV centers and the optimal implementation of demonstration-type quantum tasks in these systems. Our main focus will be the optimization of precision (fidelity) and robustness of the gate operations. This includes the protection of the quantum registers against environmental noise as well as the design and implementation of gates that are insensitive to experimental imperfections, such as deviations in the amplitudes of control fields. In the past, we have made excellent progress towards this goal, mostly working with single quantum bits. In the present project, we will focus on extending these results to multi-qubit systems, in particular hybrid systems consisting of electronic as well as nuclear spins.