Enhancement of blackbody friction due to the finite lifetime of atomic levels.
Enhancement of blackbody friction due to the finite lifetime of atomic levels.
复制标题
由于原子能级的寿命有限，黑体摩擦力增强。
DOI：
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发表时间：
2012
影响因子：
8.6
通讯作者：
U. Jentschura
中科院分区：
文献类型：
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作者：
Grzegorz Łach;M. Dekieviet;U. Jentschura
作用在相对于热光子浴移动的原子上的热摩擦力已知与频率相关的原子（偶极）极化率的虚部上的积分成比例。使用数值方法，我们发现，原子上的黑体摩擦无论是在稀释环境中，还是在热炉是大于以前认为的数量级。这种增强是由于低频热辐射对跃迁的远非共振驱动。在典型温度下，黑体辐射最大值远低于原子跃迁波长。令人惊讶的是，由于原子能级的有限寿命，这引起了洛伦兹线轮廓，远离共振激发导致黑体摩擦的主要贡献。
The thermal friction force acting on an atom moving relative to a thermal photon bath is known to be proportional to an integral over the imaginary part of the frequency-dependent atomic (dipole) polarizability. Using a numerical approach, we find that blackbody friction on atoms either in dilute environments or in hot ovens is larger than previously thought by orders of magnitude. This enhancement is due to far off-resonant driving of transitions by low-frequency thermal radiation. At typical temperatures, the blackbody radiation maximum lies far below the atomic transition wavelengths. Surprisingly, due to the finite lifetime of atomic levels, which gives rise to Lorentzian line profiles, far off-resonant excitation leads to the dominant contribution for blackbody friction.