论文标题
比较两个多路复用的便携式冷原子真空标准
Comparison of two multiplexed portable cold-atom vacuum standards
论文作者
论文摘要
储层计算是预测湍流的有力工具，其简单的架构具有处理大型系统的计算效率。然而，其实现通常需要完整的状态向量测量和系统非线性知识。我们使用非线性投影函数将系统测量扩展到高维空间，然后将其输入到储层中以获得预测。我们展示了这种储层计算网络在时空混沌系统上的应用，该系统模拟了湍流的若干特征。我们表明，使用径向基函数作为非线性投影器，即使只有部分观测并且不知道控制方程，也能稳健地捕捉复杂的系统非线性。最后，我们表明，当测量稀疏、不完整且带有噪声，甚至控制方程变得不准确时，我们的网络仍然可以产生相当准确的预测，从而为实际湍流系统的无模型预测铺平了道路。
We compare the vacuum measured by two portable cold-atom vacuum standards (pCAVS) based on ultracold $^7$Li atoms. The pCAVS are quantum-based standards that use a priori scattering calculations to convert a measured loss rate of cold atoms from a conservative trap into a background gas pressure. Our pCAVS devices share the same laser system and measure the vacuum concurrently. The two pCAVS together detected a leak with a rate on the order of $10^{-6}$ Pa L/s. After fixing the leak, the pCAVS measured a pressure of about 40 nPa with 2.6 % uncertainty. The two pCAVS agree within their uncertainties, even when swapping some of their component parts. Operation of the pCAVS was found to cause some additional outgassing, on the order of $10^{-8}$ Pa L/s, which can be mitigated in the future by better thermal management.
