Fraunhofer Diffraction of Atomic Matter Waves: Electron Transfer Studies with a Laser Cooled Target

Abstract

We have constructed an apparatus combining the experimental techniques of cold target recoil ion momentum spectroscopy and a laser cooled target. We measure angle differential cross sections in Li(+)+Na-->Li+Na(+) electron transfer collisions in the keV energy regime with a momentum resolution of 0.12 a.u. yielding an order of magnitude better angular resolution than previous measurements. We resolve Fraunhofer-type diffraction patterns in the differential cross sections. Good agreement with predictions of the semiclassical impact parameter method is obtained.

Self-interfering matter-wave patterns generated by a moving laser obstacle in a two-dimensional Bose-Einstein condensate inside a power trap cut off by box potential boundaries

“…Similarly, we can argue that the crosslike matter-wave pattern observed in our Fig. 1 above, is also analogous to the Fraunhofer diffraction pattern [37].…”

Atomic-matter-wave diffraction evidenced in low-energy Na++Rb charge-exchange collisions

“…In this respect, the advent of cold-target recoil-ion spectroscopy (COLTRIMS [6]) has been a breakthrough since it allows measurements of differential cross sections with unprecedented resolution. An additional step forward has been achieved as COLTRIMS has been coupled to laser-cooled atomic targets trapped in a magneto-optical trap (MOT) [7][8][9]. The resulting MOTRIMS setup indeed provides stateselective differential cross sections, with hitherto unsurpassed accuracy, due to the extremely low target cloud temperature.…”

“…The resulting MOTRIMS setup indeed provides stateselective differential cross sections, with hitherto unsurpassed accuracy, due to the extremely low target cloud temperature. Many experiments have been performed worldwide [7][8][9][10][11][12][13][14][15][16], using alkali-metal atomic targets, and have revealed detailed information on single-and multielectron capture processes.…”

“…For instance, MOTRIMS experiments have resolved oscillatory patterns in the differential cross sections associated to single charge transfer in low-energy Li + + Na collisions [7]. These oscillations have been interpreted in terms of Fraunhofer diffraction of atomic matter waves by analogy with usual diffraction of light waves: The incoming projectile ion, with de Broglie wavelength λ, catches an electron from the target atom provided the impact parameter b is smaller than a typical value b max , so that the target acts as a "hole" of radial aperture b max ; angular diffraction patterns with λ/2b max characteristic spacing then follow.…”

Oscillatory patterns in angular differential ion-atom charge exchange cross sections: The role of electron saddle swaps

“…By the year 2000, studies involving processes like state selective charge exchange, atomic photodouble-ionization and fully differential atomic single ionization, clearly showed the underlying potential of this novel technique. Such an advance also led to the development of new techniques, like the magnetooptical trap recoil-ion momentum spectroscopy (MOTRIMS) [7][8][9] in which a target that is laser cooled and magnetically trapped is used in the reaction microscope. By using this technique, during the last few years the KVI group succeeded in obtaining nstate selective charge exchange cross sections for ion collisions with Na(3s) and Na*(3p) [10].…”