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arXiv · 1409.0365

Tunable sub-luminal propagation of narrowband x-ray pulses

K. P. Heeg·J. Haber·D. Schumacher·L. Bocklage·H. -C. Wille·K. S. Schulze·R. Loetzsch·I. Uschmann·G. G. Paulus·R. Rüffer·R. Röhlsberger·J. Evers
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Abstract

Group velocity control is demonstrated for x-ray photons of 14.4 keV energy via a direct measurement of the temporal delay imposed on spectrally narrow x-ray pulses. Sub-luminal light propagation is achieved by inducing a steep positive linear dispersion in the optical response of ${}^{57}$Fe Mössbauer nuclei embedded in a thin film planar x-ray cavity. The direct detection of the temporal pulse delay is enabled by generating frequency-tunable spectrally narrow x-ray pulses from broadband pulsed synchrotron radiation. Our theoretical model is in good agreement with the experimental data.

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K. P. Heeg, J. Haber, D. Schumacher, L. Bocklage, H. -C. Wille, K. S. Schulze, R. Loetzsch, I. Uschmann, G. G. Paulus, R. Rüffer, R. Röhlsberger, J. Evers. 2014-09-01. Tunable sub-luminal propagation of narrowband x-ray pulses. https://doi.org/10.1103/physrevlett.114.203601

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