论文标题
部分可观测时空混沌系统的无模型预测
Optimal microwave control pulse for nuclear spin polarization and readout in dense nitrogen-vacancy ensembles in diamond
论文作者
论文摘要
拥有核自旋的氮散布中心是新型核自旋陀螺仪的有希望的候选者。制备核自旋状态是实施利用核旋转的传感器的关键步骤。在低磁场中，这样的制剂利用种群转移，使用微波脉冲从极化电子自旋到核自旋。当磁性转变无法很好地解决时，较早提出的窄带微波脉冲的使用效率低下，尤其是当应用于具有自然丰富碳原子或氮 - 降低中心的致密整合的钻石时。在这项研究中，作者对3种相对易于访问的脉冲形状进行了优化的脉冲形状。对一系列磁过渡线的优化进行了优化，对应于实际上重要的氮浓度范围（5-50 ppm）。已经发现，在低氮浓度下，优化的脉冲却很少添加到简单的平方形脉冲中，并且在密集的氮 - 呈胶合体的情况下，观察到目标状态人群的磁性转变宽度相当广泛为1.5 MHz的最佳脉冲，而目标状态的提高了15％。
Nitrogen-vacancy centers possessing nuclear spins are promising candidates for a novel nuclear spin gyroscope. Preparation of a nuclear spin state is a crucial step to implement a sensor that utilizes a nuclear spin. In a low magnetic field, such a preparation utilizes population transfer, from polarized electronic spin to nuclear spin, using microwave pulses. The use of the narrowband microwave pulse proposed earlier is inefficient when magnetic transitions are not well resolved, particularly when applied to diamond with a natural abundance of carbon atoms or dense ensembles of nitrogen-vacancy centers. In this study, the authors performed optimization of the pulse shape for 3 relatively easily accessible pulse shapes. The optimization was done for a range of magnetic transition linewidths, corresponding to the practically important range of nitrogen concentrations (5-50 ppm). It was found that, while at low nitrogen concentrations, optimized pulse added very little to simple square shape pulse, and in the case of dense nitrogen-vacancy ensembles, with a rather wide magnetic transition width of 1.5 MHz optimal pulses, a factor of 15% improvement in the population of the target state was observed.
