论文标题
高灵敏度加速度测定法具有磁性冷却的微球
High sensitivity accelerometry with a feedback-cooled magnetically levitated microsphere
论文作者
论文摘要
我们表明，高真空中的磁性微球可以通过比较其与市售地球通的响应来用作加速度计。该系统显示出对超高加速度敏感性的巨大希望，而无需大量质量或低温。通过反馈冷却，瞬态衰减时间会减少，并将质量中心运动冷却至\ si {9} {k}或更少。值得注意的是，悬浮的粒子加速度计具有敏感性降低至\ si {3.6e-8} {\ Mathit {\ Mathit {g}/\ sqrt {hz}}}}，并给出了类似于\ si {14} {14} {HZ} {hz}的频率相似的测量值，尽管该频率较小，但较小的尺寸是较小的。在校准中没有免费参数，加速度计的响应匹配\ num {3} \％at \ si {5} {Hz}。由于\ si {0.25} {\ upmu g}的粒子质量相对较大，该系统达到了这种敏感性，\ si {1.75} {1.75} {hz}的质量振荡频率的低中心以及一种新型的图像分析方法，可以用\ si {1.6} nm a image a imake nm a imake actacemention。
We show that a magnetically levitated microsphere in high vacuum can be used as an accelerometer by comparing its response to that of a commercially available geophone. This system shows great promise for ultrahigh acceleration sensitivities without the need for large masses or cryogenics. With feedback cooling, the transient decay time is reduced and the center-of-mass motion is cooled to \SI{9}{K} or less. Remarkably, the levitated particle accelerometer has a sensitivity down to \SI{3.6e-8}{\mathit{g}/\sqrt{Hz}} and gives measurements similar to those of the commercial geophone at frequencies up to \SI{14}{Hz} despite a test mass that is four billion times smaller. With no free parameters in the calibration, the responses of the accelerometers match within \num{3}\% at \SI{5}{Hz}. The system reaches this sensitivity due to a relatively large particle mass of \SI{0.25}{\upmu g}, a low center of mass oscillation frequency of \SI{1.75}{Hz}, and a novel image analysis method that can measure the displacement with an uncertainty of \SI{1.6}{nm} in a single image.
