Kilic Velat, DiMarco Christopher S, Diamond Jacob M, Chu Pinghan, Ramesh K T, Wang Zhehui, Foster Mark A
Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA.
Hopkins Extreme Materials Institute, Johns Hopkins University, Baltimore, MD, USA.
Nat Commun. 2024 Sep 4;15(1):7732. doi: 10.1038/s41467-024-52094-y.
Capturing extreme surface velocities with >50 km/s dynamic range, which arise in shock physics such as inertial confinement fusion (ICF), is beyond the reach of conventional photon Doppler velocimetry (PDV) systems due to the need for extremely large electrical bandwidth under such conditions. The recent ignition in ICF calls for new velocimetry that can measure velocities exceeding 100 km/s. Time lens PDV (TL-PDV) is a solution where the high frequency beat signal from a conventional PDV system is periodically temporally magnified in the optical domain using a time lens. Here we experimentally demonstrate TL-PDV for the first time, validate the performance over a 74 km/s velocity range with high accuracy using a temporal magnification factor of 7.6, and verify excellent agreement with conventional PDV for laser driven micro-flyer experiments. TL-PDV currently provides the largest velocity dynamic range among PDV systems and is scalable to even higher velocities, which makes it an ideal candidate for material characterization under the most extreme conditions such as optimizing fuel efficiency in ICF experiments.
捕捉动态范围大于50 km/s的极端表面速度是传统光子多普勒测速（PDV）系统无法企及的，这种速度出现在诸如惯性约束聚变（ICF）等冲击物理领域，因为在这种条件下需要极大的电带宽。ICF领域最近的点火实验要求有新的测速技术能够测量超过100 km/s的速度。时间透镜PDV（TL-PDV）是一种解决方案，其中来自传统PDV系统产生的高频拍频信号利用时间透镜在光学域中进行周期性时间放大。在此，我们首次通过实验演示了TL-PDV，使用7.6的时间放大因子在74 km/s的速度范围内高精度地验证了其性能，并在激光驱动微飞片实验中验证了与传统PDV的高度一致性。目前，TL-PDV在PDV系统中提供了最大的速度动态范围，并且可以扩展到更高的速度，这使其成为在最极端条件下进行材料表征的理想选择，比如在ICF实验中优化燃料效率。
