482 citations · 994 across the 21 of their papers we have counts for
22 papers
Efficient prediction of attosecond two-colour pulses from an X-ray free-electron laser with machine learning
Karim K. Alaa El-Din, Oliver G. Alexander, Leszek J. Frasinski +12
X-ray free-electron lasers are sources of coherent, high-intensity X-rays with numerous applications in ultra-fast measurements and dynamic structural imaging. Due to the stochasti…
A Rate Model of Electron Populations for Non-linear High-Fluence X-ray Absorption Near-Edge Spectra
Robin Y. Engel, Markus Scholz, Jan O. Schunck +1
Absorbing a focused, femtosecond X-ray pulse from a Free-Electron Laser (FEL) can lead to extreme electronic excitations in solids. This excitation drives changes of the electronic…
Electron Dynamics at High-Energy Densities in Nickel from Non-linear Resonant X-ray Absorption Spectra
Robin Y. Engel, Oliver Alexander, Kaan Atak +40
The pulse intensity from X-ray free-electron lasers (FELs) can create extreme excitation densities in solids, entering the regime of non-linear X-ray-matter interactions. We show L…
The mechanism of high harmonic generation in liquid alcohol
Oliver Alexander, Jonathan C. T. Barnard, Esben W. Larsen +10
The observation of non-perturbative harmonic emission in solids from ultrashort laser pulses [1] sparked a wave of studies [2,3] as a probe of charge carrier dynamics in solids und…
Temporal characterization of long quantum-path high harmonics
A. Carpeggiani, B. Bodi, E. S. Skantzakis +5
We measure for the first time the duration of long-quantum path EUV high harmonics produced in xenon gas. The long-quantum path contribution to the high-harmonic signal was careful…
Attosecond Coherent Electron Motion in Auger-Meitner Decay
Siqi Li, Taran Driver, Philipp Rosenberger +38
In quantum systems, coherent superpositions of electronic states evolve on ultrafast timescales (few femtosecond to attosecond, 1 as = 0.001 fs = 10^{-18} s), leading to a time dep…
Correlation Driven Transient Hole Dynamics Resolved in Space and Time in the Isopropanol Molecule
T. Barillot, O. Alexander, B. Cooper +46
The possibility of suddenly ionized molecules undergoing extremely fast electron hole dynamics prior to significant structural change was first recognized more than 20 years ago an…
Electronic Quantum Coherence in Glycine Molecules Probed with Ultrashort X-ray Pulses in Real Time
David Schwickert, Marco Ruberti, Přemys Kolorenč +25
Quantum coherence between electronic states of a photoionized molecule and the resulting process of ultrafast electron-hole migration have been put forward as a possible quantum me…
Two-dimensional partial covariance mass spectrometry for the top-down analysis of intact proteins
Taran Driver, Vitali Averbukh, Leszek J. Frasinski +2
Two-dimensional partial covariance mass spectrometry (2D-PC-MS) exploits the inherent fluctuations of fragment ion abundances across a series of tandem mass spectra, to identify co…
Optical Parametric Amplification of Mid-Infrared Few-Cycle Pulses
Adam S Wyatt, Paloma Matía-Hernando, Allan S Johnson +8
We describe Ti:Sapphire pumped optical parametric amplification of carrier-envelope phase stabilized few-cycle (fs) mid-infrared pulses in type I -barium borate. Experiment…
Attosecond Transient Absorption Spooktroscopy: a ghost imaging approach to ultrafast absorption spectroscopy
Taran Driver, Siqi Li, Elio G. Champenois +38
The recent demonstration of isolated attosecond pulses from an X-ray free-electron laser (XFEL) opens the possibility for probing ultrafast electron dynamics at X-ray wavelengths.…
Tunable Isolated Attosecond X-ray Pulses with Gigawatt Peak Power from a Free-Electron Laser
Joseph Duris, Siqi Li, Taran Driver +31
The quantum mechanical motion of electrons in molecules and solids occurs on the sub-femtosecond timescale. Consequently, the study of ultrafast electronic phenomena requires the g…
Partial covariance two-dimensional mass spectrometry for determination of biomolecular primary structure
Taran Driver, Ruth Ayers, Rüdiger Pipkorn +8
Mass spectrometry (MS) is used widely in biomolecular structural analysis and is particularly dominant in the study of proteins. Despite its considerable power, state-of-the-art pr…
Direct characterisation of tuneable few-femtosecond dispersive-wave pulses in the deep UV
Christian Brahms, Dane R. Austin, Francesco Tani +6
Dispersive wave emission (DWE) in gas-filled hollow-core dielectric waveguides is a promising source of tuneable coherent and broadband radiation, but so far the generation of few-…
Machine learning applied to single-shot x-ray diagnostics in an XFEL
A. Sanchez-Gonzalez, P. Micaelli, C. Olivier +39
X-ray free-electron lasers (XFELs) are the only sources currently able to produce bright few-fs pulses with tunable photon energies from 100 eV to more than 10 keV. Due to the stoc…
Strong-field ionization of clusters using two-cycle pulses at 1.8~m
Bernd Schütte, Peng Ye, Serguei Patchkovskii +7
The interaction of intense laser pulses with nano-scale particles leads to the production of high-energy electrons, ions, neutral atoms, neutrons and photons. Up to now, investigat…
Self-referenced characterization of space-time couplings in near single-cycle laser pulses
T. Witting, D. R. Austin, T. Barilot +5
We report on the characterization of space-time couplings in high energy sub-2-cycle 770nm laser pulses using a self-referencing single-shot method. Using spatially-encoded arrange…
Extracting an electron's angle of return from shifted interference patterns in macroscopic high-harmonic spectra of diatomic molecules
T. Das, B. B. Augstein, C. Figueira de Morisson Faria +3
We investigate high-order harmonic spectra from aligned diatomic molecules in intense driving fields whose components have orthogonal polarizations. We focus on how the driving-fie…
Carrier-envelope phase stability of hollow-fibers used for high-energy, few-cycle pulse generation
William A. Okell, Tobias Witting, Davide Fabris +9
We investigated the carrier-envelope phase (CEP) stability of a hollow-fiber setup used for high-energy, few-cycle pulse generation. Saturation of the output pulse energy is observ…
Molecular internal dynamics studied by quantum path interferences in high order harmonic generation
Amelle Zair, Thomas Siegel, Suren Sukiasyan +9
We investigate how short and long electron trajectory contributions to high harmonic emission and their interferences give access to intra-molecular dynamics. In the case of unalig…
Analytical study of four-wave mixing with large atomic coherence
E. A. Korsunsky, T. Halfmann, J. P. Marangos +1
Four-wave mixing in resonant atomic vapors based on maximum coherence induced by Stark-chirped rapid adiabatic passage (SCRAP) is investigated theoretically. We show the advantages…
Prospects for photon blockade in four level systems in the N configuration with more than one atom
Andrew D. Greentree, John A. Vaccaro, Sebastian R. de Echaniz +2
We show that for appropriate choices of parameters it is possible to achieve photon blockade in idealised one, two and three atom systems. We also include realistic parameter range…