Leibrandt D R, Heidecker J
National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
Rev Sci Instrum. 2015 Dec;86(12):123115. doi: 10.1063/1.4938282.
We describe a general purpose digital servo optimized for feedback control of lasers in atomic, molecular, and optical physics experiments. The servo is capable of feedback bandwidths up to roughly 1 MHz (limited by the 320 ns total latency); loop filter shapes up to fifth order; multiple-input, multiple-output control; and automatic lock acquisition. The configuration of the servo is controlled via a graphical user interface, which also provides a rudimentary software oscilloscope and tools for measurement of system transfer functions. We illustrate the functionality of the digital servo by describing its use in two example scenarios: frequency control of the laser used to probe the narrow clock transition of (27)Al(+) in an optical atomic clock, and length control of a cavity used for resonant frequency doubling of a laser.
我们描述了一种通用数字伺服系统，该系统针对原子、分子和光学物理实验中的激光反馈控制进行了优化。该伺服系统能够实现高达约1 MHz的反馈带宽（受320 ns总延迟限制）；高达五阶的环路滤波器形状；多输入、多输出控制；以及自动锁定获取。伺服系统的配置通过图形用户界面进行控制，该界面还提供了一个基本的软件示波器以及用于测量系统传递函数的工具。我们通过描述其在两个示例场景中的应用来说明数字伺服系统的功能：用于探测光学原子钟中(27)Al(+)窄时钟跃迁的激光的频率控制，以及用于激光共振倍频的腔的长度控制。
