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Burgdoerfer, J

Publications and source records attributed to Burgdoerfer, J.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Attosecond Two-Photon Interferometry for Doubly Excited States of Helium

We show that the correlation dynamics in coherently excited doubly excited resonances of helium can be followed in real time by two-photon interferometry. This approach promises to map the evolution of the two-electron wave packet onto experimentally easily accessible noncoincident single-electron spectra. We analyze the interferometric signal in terms of a semianalytical model which is validated by a numerical solution of the time-dependent two-electron Schroedinger equation in its full dimensionality.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2010

Rumpling of LiF(001) surface from fast atom diffraction

Quantum diffraction of fast atoms scattered from the topmost layer of surfaces under grazing angles of incidence can be employed for the analysis of detailed structural properties of insulator surfaces. From comparison of measured and calculated diffraction patterns we deduce the rumpling of the topmost surface layer of LiF(001) (i.e., an inward shift of Li{sup +} ions with respect to F{sup -} ions). The effect of thermal vibrations on the measurement of rumpling is accounted for by ab initio calculations of the mean-square vibrational amplitudes of surface ions. At room temperature this leads to a reduction of the apparent rumpling by 0.008 A. We then obtain a rumpling of (0.05{+-}0.04) A, which improves its accuracy achieved in previous work.

36 MATERIALS SCIENCE↗
DOE OSTI2010

Encoding and decoding phase information in high-n circular wave packets

We demonstrate theoretically and experimentally the extraction of detailed information on the density matrix of very-high-n (>300) near-circular Rydberg wave packets through Fourier analysis of the quantum beat and quantum revival signals. The remarkably long coherence times associated with circular wave packets facilitate the preservation and read-out of phase information encoded in this matrix. We illustrate the power of the method by determining the angular localization of the components of a wave packet.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗