William: DM: CEP stability of hollow-fibers used for high-energy, few-cycle pulse generation

We investigated the carrier-envelope phase (CEP) stability of a hollow-fiber setup used for high-energy, fewcycle pulse generation. Saturation of the output pulse energy is observed at 0:6 mJ for a 260µm inner-diameter,
1 m long fiber, statically filled with neon, with the pressure adjusted to achieve an output spectrum capable
of supporting sub-4 fs pulses. The maximum output pulse energy can be increased to 0:8 mJ by using either
differential pumping, or circularly polarized input pulses. We observe the onset of an ionization-induced CEP
instability, which does not increase beyond an input pulse energy of 1:25 mJ due to losses in the fiber caused
by ionization. There is no significant difference in the CEP stability with differential pumping compared to
static-fill, demonstrating that gas flow in differentially pumped fibers does not degrade the CEP stabilization

Dane: JC: Attosecond lighthouse

Original Lighthouse proposal / theory
http://prl.aps.org/abstract/PRL/v108/i11/e113904

Lighthouse in plasma mirror HHG:
http://www.nature.com/nphoton/journal/v6/n12/full/nphoton.2012.284.html

Lighthouse in gases:
http://www.nature.com/nphoton/journal/vaop/ncurrent/full/nphoton.2013.170.html

Laila; Ultrafast ICD in Endohedral Fullerenes, Mediated by Single and Multipole Plasmon Excitations

Emma: JC: Controlling dielectrics with the electric field of light

Modern-day computing and optical communications are limited by the speed at which signals can be turned on and off. This paper demonstrates that frequencies of the order of Petahertz could be achieved by exploiting the change in behavior from insulator to conductor of a dielectric when exposed to strong, few-cycle laser pulses. Transient absorption, streaking and reflectivity techniques are used to probe these sub-femtosecond dynamics and observe the reversibility of the changes in the dielectric.
http://www.nature.com/nature/journal/v493/n7430/full/nature11720.html

paper:
http://www.nature.com/nature/journal/v493/n7430/pdf/nature11720.pdf

supplementary information:
http://www.nature.com/nature/journal/v493/n7430/extref/nature11720-s1.pdf

Davide: VUV double whammy

Extreme-ultraviolet pump–probe studies of one-femtosecond-scale electron dynamics

http://www.nature.com/nphys/journal/v7/n10/full/nphys2033.html

Observation of Ultrafast Charge Migration in an Amino Acid

http://pubs.acs.org/doi/abs/10.1021/jz3016028

and maybe a discussion of some first results?

Thomas: Manipulation of quantum paths for space–time characterization of attosecond pulses

Attosecond extreme-ultraviolet pulses1 have a complex space–time structure2. However, at present, there is no method to observe this intricate detail; all measurements of the duration of attosecond pulses are, to some extent, spatially averaged1, 3, 4, 5. A technique for determining the full space–time structure would enable a detailed study of the highly nonlinear processes that generate these pulses as a function of intensity without averaging6, 7. Here, we introduce and demonstrate an all-optical method to measure the space–time characteristics of an isolated attosecond pulse. Our measurements show that intensity-dependent phase and quantum-path interference both play a key role in determining the pulse structure. In the generating medium, the attosecond pulse is strongly modulated in space and time. Propagation modifies but does not erase this modulation. Quantum-path interference of the single-atom response, previously obscured by spatial and temporal averaging, may enable measuring the laser-field-driven ion dynamics with sub-cycle resolution.

http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys2525.html

Thomas' slides are here

Han: Generation of EUV radiation by plasmonic field enhancement using nano-structured bowties and funnel-waveguides

Generation of EUV radiation by plasmonic field enhancement using nano-structured bowties and funnel-waveguides

Recent experimental data of high-order harmonic generation (HHG), obtained by use of the plasmonic field enhancement of nanostructure bowties and funnel-waveguides, are presented. Emphasis is laid on reproduction of previous experimental results and also elucidation of the fundamental limitations associated with the nanostructure thermal damage, small laser-gas interaction volume, and atomic line emission in the plasmon-driven HHG process. In addition, the dominance of coherent harmonics is quantitatively verified by implementing a two-beam interference experiment using a pair of funnel-waveguides. This study proves that funnel-waveguides are a superior plasmonic device capable of providing not only high thermal immunity but also sufficient atom emitters to produce practically usable extreme-ultraviolet (EUV) radiation in a reproducible manner.

http://onlinelibrary.wiley.com/doi/10.1002/andp.201200160/abstract




Han's slides