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キーワード:
-
MPINP:
Research group A. Pálffy – Division C. H. Keitel
要旨:
This thesis is dedicated to the study of collective effects of nuclei in single xray
photon superradiance. To this end we investigate aspects of superradiance
in both nuclear forward scattering and in thin-film cavities with an embedded
57Fe nuclear layer. A general theoretical framework is developed to investigate
a single-photon cooperative emission from a cloud of resonant systems, atoms or
nuclei, in the presence of magnetic hyperfine splitting. In the limit of a thick
sample, we present our results for two means to coherently control the collective
single x-ray photon emission in nuclear forward scattering. In the limit of a thin
sample in a thin-film cavity with embedded resonant nuclei, we find out that unlike
the magnetic hyperfine splitting of a single atom or nucleus, interesting collective
effects may occur which modify the hyperfine level structure. In addition, for a
certain parameter regime a spectrum reminiscent of electromagnetically induced
transparency (EIT) can be achieved. Based on this EIT-like effect, a theoretical
control mechanism for stopping x-ray pulses in the thin-film x-ray cavity is put
forward. Finally, we show theoretically that for the case of two nuclear ensembles
in the thin-film cavity, pseudo-Rabi splitting due to the strong coupling between
the two layers should occur. The latter findings are confirmed by preliminary
experimental data.
