arXiv:1410.7152 · Physical Review A

Application of the weak-measurement technique to study atom-vacuum interactions

M. Zhang, Shuqiang Zhu

Published Oct 19, 2015• 12 citations

Abstract

Quantum weak measurement has attracted much interest recently [J. Dressel et al., Rev. Mod. Phys. 86, 307 (2014).] because it could amplify some weak signals and provide a technique to observe nonclassical phenomena. Here, we apply this technique to study the interaction between the free atoms and the vacuum in a cavity. Due to the gradient field in the vacuum cavity, the external orbital motions and the internal electronic states of atoms can be weakly coupled via the atom-field electric-dipole interaction. We show that, within the properly postselected internal states, the weak atom-vacuum interaction could generate a large change to the external motions of atoms due to the postselection-induced weak values.

DOI: 10.1103/physreva.92.043825

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