The reflection of metastable argon atoms from evanescent waves produced by total internal reflection and surface-plasmon excitation is investigated. We study the departure from ideal specular reflection by comparing our experimental results with a Monte Carlo simulation of the reflection process. The observed broadening of the reflection beam was found to be caused predominantly by fluctuations of the diple force. We show that the surface plasmon produces significant enhancement of the evanescent-wave intensity without degrading the quality of reflection. In addition, the number of spontaneous emissions occurring during the reflection process was investigated by comparing the reflectivity of evanescent-wave mirrors based on open and closed transitions in argon. An open-transition mirror selectively reflects atoms which do not undergo spontaneous emission. For a large detuning, the average number of spontaneous emissions for reflected atoms was <0.11.

• Received 23 September 1993

DOI:https://doi.org/10.1103/PhysRevA.49.3814