Heidelberg 2015 – wissenschaftliches Programm
A 19.4: Vortrag
Mittwoch, 25. März 2015, 11:45–12:00, C/HSO
Line-shape manipulation for x-ray frequency-comb generation — •Stefano M. Cavaletto, Zuoye Liu, Zoltan Harman, Christian Ott, Christian Buth, Thomas Pfeifer, and Christoph H. Keitel — Max Planck Institute for Nuclear Physics, Heidelberg, Germany
Optical frequency combs had a revolutionary impact on precision spectroscopy and metrology. This was recently enabled at extreme-ultraviolet frequencies via methods based on high-harmonic generation (HHG). We put forward a three-level Λ-type scheme in which the absorption spectrum of a short pulse, tuned to an x-ray transition, is manipulated by an optical-frequency-comb laser which couples the excited state to a nearby level [S. M. Cavaletto et al., Nature Photonics 8, 520 (2014)]. The comb structure displayed by the x-ray absorption spectrum might eventually represent an alternative scheme for x-ray frequency-comb generation, overcoming the limitations of present HHG-based methods. We then present related line-shape-manipulation schemes in rubidium atoms, whose 5s 2S1/2→ 5p 2P1/2 (794.76 nm) and 5s 2S1/2→ 5p 2P3/2 (780.03 nm) transitions are simultaneously excited by pump/probe optical pulses centered at 780 nm. We model the atomic system via a three-level V-type scheme, in order to connect the absorption line shape of the two excited transitions for different time delays to the quantum evolution (in amplitude and phase) of the atomic state.