Dynamical instability of a condensate induced by a rotating thermal gas.
Dynamical instability of a condensate induced by a rotating thermal gas.
复制标题
旋转热气体引起的凝结水的动态不稳定性。
DOI：
10.1103/physrevlett.88.070401
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发表时间：
2001
影响因子：
8.6
通讯作者：
A. Griffin
中科院分区：
文献类型：
--
作者：
J. Williams;E. Zaremba;B. Jackson;T. Nikuni;A. Griffin
我们研究了轴对称阱中存在旋转热云时凝结物的表面模式。通过考虑原子在凝聚态和非凝聚态之间转移的碰撞，我们发现m>0模的阻尼比m<0模的阻尼小，m>0模的旋转方向与热云的旋转方向相同，m<0模的阻尼比m<0模的阻尼小，其中m是激发的极性。我们发现，超过一个临界角旋转频率，相当于朗道稳定性准则，m>0模式变得动态不稳定，导致涡旋成核的可能性。我们还推广我们的稳定性分析来处理的情况下，定态的凝聚已经拥有一个单一的漩涡。
We study surface modes of the condensate in the presence of a rotating thermal cloud in an axisymmetric trap. By considering collisions that transfer atoms between the condensate and the noncondensate, we find that m>0 modes, which rotate in the same sense as the thermal cloud, damp less strongly than m<0 modes, where m is the polarity of the excitation. We show that above a critical angular rotation frequency, equivalent to the Landau stability criterion, m>0 modes become dynamically unstable, leading to the possibility of vortex nucleation. We also generalize our stability analysis to treat the case where the stationary state of the condensate already possesses a single vortex.