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Specular reflection of matter waves from a rough mirror

V. Savalli·D. Stevens·J. Esteve·P. D. Featonby·V. Josse·N. Westbrook. C. I. Westbrook·A. Aspect
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Abstract

We have made a high resolution study of the specularity of the atomic reflection from an evanescent wave mirror using velocity selective Raman transitions. We have observed a double structure in the velocity distribution after reflection: a peak consistent with specular reflection and a diffuse reflection pedestal, whose contribution decreases rapidly with increasing detuning. The diffuse reflection is due to two distinct effects: spontaneous emission in the evanescent wave and a roughness in the evanescent wave potential whose amplitude is smaller than the de Broglie wavelength of the reflected atoms.

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V. Savalli, D. Stevens, J. Esteve, P. D. Featonby, V. Josse, N. Westbrook. C. I. Westbrook, A. Aspect. 2002-02-22. Specular reflection of matter waves from a rough mirror. https://doi.org/10.1103/physrevlett.88.250404

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