论文标题
临时偏移双弯曲振动仪，带有生平轴向精度
Temporal-offset dual-comb vibrometer with picometer axial precision
论文作者
论文摘要
我们展示了双弯曲振动仪，其中一个频率b的脉冲分为脉冲对。我们在样品前面的每个脉冲对的两个脉冲之间引入了一个延迟，在相应的两个连续反射在振动样品表面上，最初引入的延迟将被修改的Sagnac几何形状取消。两种脉冲之间的剩余相位差对应于两个连续反射期间表面轴向位置的变化。 Sagnac几何形状降低了相位抖动的效果，因为两个脉冲通过几乎相同的光学路径（在相反的方向）传播，并且通过时间门控消除了伪信号。我们确定轴向精度为4 pm的表面声波装置上表面振动的幅度。该技术可以高度准确地确定极小的位移。
We demonstrate a dual-comb vibrometer where the pulses of one frequency-comb are split into pulse pairs. We introduce a delay between the two pulses of each pulse pair in front of the sample, and after the corresponding two consecutive reflections at the vibrating sample surface, the initially introduced delay is cancelled by a modified Sagnac geometry. The remaining phase difference between the two pulses corresponds to the change in the axial position of the surface during the two consecutive reflections. The Sagnac geometry reduces the effect of phase jitter since both pulses propagate through nearly the same optical path (in opposite directions), and spurious signals are eliminated by time gating. We determine the amplitude of a surface vibration on a surface-acoustic-wave device with an axial precision of 4 pm. This technique enables highly accurate determination of extremely small displacements.
