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We characterized electronic dipole oscillations in chromium doped sapphire (Cr:Al2O3) using Fourier transform extreme ultraviolet attosecond spectroscopy (FTXUV) combined with an isolated attosecond pulse, which reveals the electric band-structure and dephasing process in solids. [ABSTRACT FROM AUTHOR]

Attosecond imaging with electron beams can access optical-field-driven electron dynamics in space and time. Here we report first diffraction and microscopy experiments with attosecond electron pulses. We study attosecond-level timing of Bragg-spot emission and visualize light-wave propagation in space and time. [ABSTRACT FROM AUTHOR]

We demonstrate the generation and optical control of ultrashort high-coherence electron pulses. The free-electron quantum state is phase-modulated in the longitudinal and transverse dimensions, and the formation of attosecond electron pulse trains is quantitatively probed. [ABSTRACT FROM AUTHOR]

We employ a pair of single-cycle near-infrared pulses to control coherent transfer of single electrons between the contacts of a plasmonic nanocircuit. As a result, attosecond and highly nonlinear phenomena occur at pJ pulse energies. [ABSTRACT FROM AUTHOR]

Attosecond time-resolved photoemission from the differently terminated BiTeCl surfaces yield a photoelectron streaking that cannot be explained by bulk propagation effects alone. Instead, the atomic scale electronic structure and dynamical screening for both surface terminations have to be taken into account. [ABSTRACT FROM AUTHOR]

The unprecedented combination of transient absorption and ion mass spectroscopy with attosecond resolution is used to study and control the complex multidimensional excitation and decay cascade of an ultrafast Auger process in krypton. [ABSTRACT FROM AUTHOR]

A time resolved setup combining sub-2fs UV pump pulses with attosecond XUV probe pulses is presented. This scheme will allow the UV photo-induced electron dynamics in bio-chemically relevant molecules to be investigated with unprecedented time resolution. [ABSTRACT FROM AUTHOR]

Minimizing the CEP jitter of isolated attosecond pulses (IAP) will be important for future applications. This jitter is experimentally and theoretically investigated and can be minimized when the driving pulse is near its Fourier limit but with slightly negative chirp. Thus, understanding and characterization of the CEP jitter of IAPs is a first step towards exact control of the electric field of IAP pulses. [ABSTRACT FROM AUTHOR]

Time-dependent Schrodinger equation simulations for a one-dimensional model potential reveal that the delay extracted from a streaking spectrogram does not reflect the photoemission time if the streaking field inside the solid cannot be neglected. [ABSTRACT FROM AUTHOR]

We show theoretically and by simulations how coherent transition radiation from tilted surfaces can be used for characterization of attosecond free-electron pulses such as used for pump-probe electron microscopy and diffraction. The tilted geometries eliminate velocity-mismatch and beam-diameter effects, providing sensitivity to attosecond times even for almost arbitrarily large beam diameters. [ABSTRACT FROM AUTHOR]

Extreme-ultraviolet pulses as short as 5 fs, produced by high-order harmonic generation and selected by a time-delay compensated monochromator, were fully reconstructed thanks to an advanced ptychographic technique, while most commonly used reconstruction methods fail. These pulses constitute the shortest extreme ultraviolet pulses ever achieved via a time-delay compensated monochromator. [ABSTRACT FROM AUTHOR]

Attosecond streaking with broadband SXR continua leads to contributions from multiple overlapping lines in the photoelectron spectrum. The Volkov-transform generalized projection algorithm (VTGPA) is generalised to include all contributing photoelectron bands (multi-line VTGPA) for the reconstruction of ultra-broadband SXR continua. We further investigate the influence of the collection angle of photoelectron detectors on attosecond streaking spectrograms and show full reconstruction for angle-integrated streaking traces. Also, the effects of the photoionization dipole matrix elements on the reconstruction are demonstrated. [ABSTRACT FROM AUTHOR]

We demonstrate up to two orders of magnitude enhancements in high harmonic generation efficiency via sub-cycle control and scaling of the ionization rate in a two colour laser field. [ABSTRACT FROM AUTHOR]

We demonstrate the on-target temporal characterization of sub-4-fs pulses by third-harmonic dispersion-scan, using a minimal in-line setup where a gas target optimized for high-harmonic generation doubles as nonlinear medium, obtaining excellent agreement with independent SEA-F-SPIDER measurements. [ABSTRACT FROM AUTHOR]