Finite-temperature theory of the scissors mode in a Bose gas using the moment method
Finite-temperature theory of the scissors mode in a Bose gas using the moment method
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使用矩法的玻色气体剪刀模的有限温度理论
DOI：
10.1103/physreva.65.033611
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发表时间：
2001
影响因子：
2.9
通讯作者：
T. Nikuni
中科院分区：
文献类型：
--
作者：
T. Nikuni
本文用广义Gross-Pitaevskii方程和半经典动力学方程讨论了有限温度下玻色凝聚态气体中的剪刀模。这两个方程都考虑了凝聚态原子和非凝聚态原子碰撞的影响。我们解决耦合力矩方程描述的四极矩的凝聚体和非凝聚体组件的振荡，找到集体模式的频率和碰撞阻尼率作为温度的函数。我们的计算推广了Gu\'ery-Odelin和Stringari在T=0和正常相的计算。它们补充了杰克逊和Zaremba的数值结果，虽然朗道阻尼是我们的方法。我们的结果也被用来计算四极响应函数，这是有关的转动惯量。它明确示出，在有限温度下的被困玻色气体的转动惯量涉及的总和的无旋组件从冷凝物和旋转组件从热云原子。
We use a generalized Gross-Pitaevskii equation for the condensate and a semiclassical kinetic equation for the noncondensate atoms to discuss the scissors mode in a trapped Bose-condensed gas at finite temperatures. Both equations include the effect of collisions between the condensate and noncondensate atoms. We solve the coupled moment equations describing oscillations of the quadrupole moments of the condensate and noncondensate components to find the collective-mode frequencies and collisional damping rates as a function of temperature. Our calculations extend those of Gu\'ery-Odelin and Stringari at $T=0$ and in the normal phase. They complement the numerical results of Jackson and Zaremba, although Landau damping is left out of our approach. Our results are also used to calculate the quadrupole response function, which is related to the moment of inertia. It is shown explicitly that the moment of inertia of a trapped Bose gas at finite temperatures involves a sum of an irrotational component from the condensate and a rotational component from the thermal-cloud atoms.