Evanescent-wave mirror

movie of bouncing atoms Evanescent waves (EW) are a very versatile instrument to manipulate cold atoms. We have used evanescent waves as a mirror for cold atoms, to cool atoms, to load them into an optical dipole trap, and to probe atoms near the surface. An EW occurs when a laser beam undergoes total internal reflection on an interface between a dielectric (glass) and vacuum. On the vacuum side the light decays exponentially on the scale of the wavelength, thus forming a very thin "layer of light" on the surface.

We study reflection of atoms from evanescent waves, with the ultimate goal to create a low-dimensional quantum gas of ultracold atoms, following the proposal described here (pdf, 310kB). Some tutorial information is listed here:

Some of our more recent results:

Radiation pressure of evanescent waves (pdf, 219 kB)
Rainbow of cold atoms (pdf, 244 kB)
Guiding of cold atoms by a red detuned laser beam (pdf, 256 kB)
Detection of trapped atoms by evanescent wave absorption
Describes the trapping of atoms in an standing wave optical dipole trap close to a dielectric surface. This was detected by a novel diagnostic method, the absorption of resonant evanescent probe light.
Overview paper (pdf, 202 kB)