Berlin 2001 – wissenschaftliches Programm
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Q: Quantenoptik
Q 1: Poster: Atom Optics
Q 1.3: Poster
Montag, 2. April 2001, 12:30–15:00, AT2
H-Atom Interferometry: a novel scanning probe — •Frank Lang and Maarten DeKieviet — Physikalisches Institut, Universität Heidelberg, Germany
Recently, we introduced the method of Atomic Beam Spin Echo (ABSE), which enables us to perform scattering experiments with an extremely high resolution in energy. Whereas this longitudinal spin echo technique zooms in on correlations within the target in time only, a transversal arrangement of the spin precession fields with respect to the atomic beam axis opens up the possibility for measuring correlations in both 2D-space and time directly. In this scattering method, we manipulate the magnetic moments in the atomic beam so as to directly compare the internal quantum state before and after scattering of each particle individually: ABSE is a working example of atom interferometry.
The basic idea of the experiment, illustrated for a spin-1/2 particle, is the following: A polarized atomic beam traverses a magnetic field which is perpendicular to both the beam and the polarization axis. The two eigenstates with respect to the quantisation axis given by the magnetic field drift apart longitudinally and transversally. Therefore, they are scattered from the sample at different points in space and time. In the second magnetic field area pointing antiparallel to the first one, the eigenstates change roles and are brought to coherently overlap again. The resulting polarisation then is a measure of the correlations at the sample in both space (10−10m - 10−6m) and time (10−13s - 10−9s). We present extensive data from our H-Atom Interferometer, stipulating the sensitivity of the method.