Shapes of rotating superfluid helium nanodroplets
Shapes of rotating superfluid helium nanodroplets
复制标题
DOI：
10.1103/physrevb.95.064510
复制
发表时间：
2017-02-16
影响因子：
3.7
通讯作者：
Vilesov, Andrey F.
中科院分区：
文献类型：
--
作者：
Bernando, Charles;Tanyag, Rico Mayro P.;Vilesov, Andrey F.
旋转超流氦液滴直径约1 μ m，获得在自由喷嘴束扩展液体氦在真空中，并研究了单次拍摄相干衍射成像使用的X射线自由电子激光。强烈变形的液滴的形成是由所获得的衍射图像中的大的各向异性和强度异常（条纹）证明。图像的分析显示，除了先前描述的轴对称扁球形形状之外，一些液滴呈现扁长形形状。的衍射图像的正演模拟表明，旋转的超流液滴的形状是非常相似的，他们的经典同行，直接访问的液滴角动量和角速度。对各向异性图像的径向强度分布和外观统计的分析证实了具有超过经典分叉阈值的大角动量的扁亚稳超流液滴的存在。
Rotating superfluid He droplets of approximately 1 mu m in diameter were obtained in a free nozzle beam expansion of liquid He in vacuum and were studied by single-shot coherent diffractive imaging using an x-ray free electron laser. The formation of strongly deformed droplets is evidenced by large anisotropies and intensity anomalies (streaks) in the obtained diffraction images. The analysis of the images shows that in addition to previously described axially symmetric oblate shapes, some droplets exhibit prolate shapes. Forward modeling of the diffraction images indicates that the shapes of rotating superfluid droplets are very similar to their classical counterparts, giving direct access to the droplet angular momenta and angular velocities. The analyses of the radial intensity distribution and appearance statistics of the anisotropic images confirm the existence of oblate metastable superfluid droplets with large angular momenta beyond the classical bifurcation threshold.