van der Waals interaction of excited media
van der Waals interaction of excited media
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激发介质的范德华相互作用
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
Y. Sherkunov
中科院分区：
文献类型：
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作者：
Y. Sherkunov
借助于依赖于介质介电常数的Lifshitz公式，很好地描述了两个基态原子介质之间的Casimir相互作用。我们将证明这个公式与激发态原子的实验证据相矛盾。我们计算了两个原子中的一个或两个被激发时它们之间的Casimir力。我们使用量子电动力学的方法，特别是衍生的问题。它使我们能够考虑原子的激发态辐射宽度。然后计算了基态原子激发态与介质间的作用力。所得结果与其他作者用微扰理论或线性响应理论得到的结果一致。将我们的结果推广到两个激发原子介质之间的相互作用的情况，得到一个公式，该公式不仅在定量上，而且在定性上与Lifshitz公式相矛盾。如果考虑基态原子的介质，这种矛盾就消失了。此外，我们的结果不包括介质的介电常数。它包括一个不同于介电常数的量，只适用于受激原子。我们的结果的主要特点如下。相互作用是共振的，根据不同介质原子的共振频率，力可以是吸引力或排斥力，Casimir力的值可能比Lifshitz公式预测的大几个数量级。这里所提到的功能是在协议与已知的实验和理论证据获得了许多作者为一个单一的激发原子与电介质的相互作用。«少
The Casimir interaction between two media of ground-state atoms is well described with the help of the Lifshitz formula depending upon the permittivity of the media. We will show that this formula is in contradiction with experimental evidence for excited atoms. We calculate the Casimir force between two atoms if one or both of them are excited. We use methods of quantum electrodynamics specially derived for the problem. It enables us to take into account the excited-state radiation widths of atoms. Then we calculate the force between the excited atom and medium of ground-state atoms. The results are in agreement with the ones obtained by other authors who used perturbation theory or linear response theory. Generalization of our results to the case of the interaction between two media of excited atoms results in a formula, which is in not only in quantitative, but in qualitative contradiction with the Lifshitz formula. This contradiction disappears if the media of ground-state atoms are considered. Moreover, our result does not include the permittivity of the media. It includes a quantity which differs from the permittivity only for excited atoms. The main features of our results are as follows. The interaction is resonant, the forcemore » may be either attractive or repulsive depending on the resonant frequencies of the atoms of different media, and the value of the Casimir force may be several orders of magnitude lager than that predicted by the Lifshitz formula. The features mentioned here are in agreement with known experimental and theoretical evidence obtained by many authors for the interaction of a single excited atom with dielectric media.« less