title: Experimental observation of quantum reflection far from threshold.
abstract: We present first experimental evidence for quantum reflection, originating exclusively from an attractive potential between an atom and a solid surface, at energies far from the threshold E(i)-->0. The system of light and stable 3He atoms scattering from an alpha-quartz crystal allows confirmation of recent theory on quantum reflection up to its asymptotic behavior, determined by the nonretarded van der Waals potential -C(3)/r(3). From the data, the gas-solid interaction potential is deduced quantitatively, covering the energy region, in which retardation plays a role.
authors: Physikalisches Institut, Heidelberg University, 69120 Heidelberg, Germany.
authors: V
authors: V
authors: Druzhinina
authors: M
authors: M
authors: DeKieviet