We consider the problem of decoherence in a Bose – Einstein condensate (BEC) of noninteracting atoms during interferometric probing with a classical monochromatic external field. The condensate is located in one of the arms of the Mach – Zehnder interferometer, while part of the radiation from the interferometer output is fed back to the input, thereby closing the coherent feedback loop. A more general setting of the problem is also considered, in which the condensate is located in a system of interferometers 'nested' into each other, while part of the output radiation of each of them is also fed back to its input, closing the so-called multiloop feedback. The possibility of effective control of decoherence rates of various matrix elements is shown. The application of feedback of the proposed type to BEC in a double-well potential is investigated. It is found that this feedback allows efficient control of the distribution of atoms between the wells.

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控制玻色 - 爱因斯坦原子凝聚与干涉反馈传感

我们考虑在经典单色外场干涉探测期间非相互作用原子的玻色-爱因斯坦凝聚体 (BEC) 中的退相干问题。冷凝物位于马赫-曾德干涉仪的一个臂中，而来自干涉仪输出的部分辐射被反馈到输入，从而关闭相干反馈回路。还考虑了该问题的更一般设置，其中冷凝物位于相互“嵌套”的干涉仪系统中，而每个干涉仪的部分输出辐射也反馈到其输入，从而关闭了- 称为多回路反馈。显示了有效控制各种矩阵元素的退相干率的可能性。研究了所提出类型的反馈在双阱电位中对 BEC 的应用。发现这种反馈允许有效控制阱之间的原子分布。