Observation of radiation pressure exerted by evanescent waves

Abstract

We report a direct observation of radiation pressure, exerted on cold rubidium atoms while bouncing on an evanescent-wave atom mirror. We analyze the radiation pressure by imaging the motion of the atoms after the bounce. The number of absorbed photons is measured for laser detunings ranging from 190 MHz to 1.4 GHz and for angles from 0.9 mrad to 24 mrad above the critical angle of total internal reflection. Depending on these settings, we find velocity changes parallel with the mirror surface, ranging from 1 to 18 cm/s. This corresponds to 2 to 31 photon recoils per atom. These results are independent of the evanescent-wave optical power.

Flexible Optical Dipole Mirror for Cold Atoms

“…The setup will be used to investigate the evanescent wave radiation pressure acting on reflecting atoms. In particular, the incoherent photon scattering close to resonance will be measured for relatively weak additional evanescent wave, extending previous far-off-resonance measurements [21]. Providing that the on-surface intensity of this auxiliary evanescent wave lies in the range of 0.1 to 100I sat (I sat being the saturation intensity), the average number of scattered photons per bounce is 0.4 to 117 respectively, for dipole mirror parameters similar to the ones described in previous sections.…”

Control of matter-wave solitons using an accelerating atomic mirror

“…Here, the mirror potential is U(x, t) = V mir (l ⊥ x, ω ⊥ t)/hω ⊥ . We refer to the previous experimental setup in reference [31], as shown in figure 1(a). The BECs is placed at the left side of device and moves towards the right to collide the atomic mirror.…”

Resolved diffraction patterns from a reflection grating for atoms

“…Our results are also significant from the point of view of measurements of the roughness of atomic mirrors. These measurements have been performed for both magnetic and evanescent wave mirrors [19,20,21,22,23]. Some of the interpretation of these measurements relies on theoretical treatments developed in close analogy with the theory of atom diffraction [24], and it is clearly useful to make additional tests of the theory when possible.…”