Observation of a second-sound-like mode in superfluid-filled aerogel
Observation of a second-sound-like mode in superfluid-filled aerogel
复制标题
超流体填充气凝胶中第二声音模式的观察
DOI：
10.1103/physrevlett.66.1878
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发表时间：
1991
影响因子：
8.6
通讯作者：
J. Maynard
中科院分区：
文献类型：
--
作者：
M. McKenna;T. Slawecki;J. Maynard
超流体在声学上很有趣，因为它可以支持多种声音传播模式，这些模式可以用来研究临界性质。最近，人们对充满超流体的气凝胶感兴趣，但对于这种可压缩材料，人们没有观察到普通的(第四)声；相反，存在介于第一和第四声之间的模式和类似第二声的模式。我们给出了气凝胶第二类声模的理论和首次观测，这一理论很重要，因为它在临界温度附近传播。
Superfluid $^{4}\mathrm{He}$ is interesting acoustically because it can support more than one mode of sound propagation, and these can be used to study critical properties. Recently, there has been interest in superfluid-filled aerogels, but for such compressible materials one does not observe the ordinary (fourth) sound; instead there is a mode intermediate between first and fourth sound and a second-sound-like mode. We present a theory for the modes and the first observation of the aerogel second-sound-like mode, which is important because it propagates near the critical temperature.