Related papers: Polarization-Resolved Core Exciton Dynamics in LiF…
Ultrafast laser excitation can trigger multiplex coherent dynamics in molecules. Here, we report attosecond transient absorption experiments addressing simultaneous probing of electronic and vibrational dynamics in a prototype molecule,…
Extreme ultraviolet (XUV) light sources allow for the probing of bound electron dynamics on attosecond scales, interrogation of high-energy-density matter, and access to novel regimes of strong-field quantum electrodynamics. Despite the…
It has long been recognised that quasi-periodic oscillations (QPOs) in the X-ray light curves of accreting black hole and neutron star binaries have the potential to be powerful diagnostics of strong field gravity. However, this potential…
Residual strain plays a critical role in determining the crystalline quality of nitride epitaxial layers and in modifying their band structure; this often leads to several interesting physical phenomena. It is found, for example, that…
We show that electrons recolliding with the ionic core upon tunnel ionization of noble gas atoms driven by a strong circularly polarized laser field in combination with a counter-rotating second harmonic are spin polarized and that their…
The use of advanced X-ray sources plays a key role in the study of dynamic processes in magnetically ordered materials. The progress in X-ray free electron lasers enables the direct and simultaneous observation of the femtosecond evolution…
We apply attosecond transient absorption spectroscopy (ATAS) to explore the effects of a nonzero permanent dipole on electron dynamics at the subfemtosecond scale, exemplified in the polar LiF molecule. In contrast with nonpolar systems, a…
Collective optical excitations in dipole-coupled nanorings of sub-wavelength spaced quantum emitters exhibit extreme sub-radiance and field confinement facilitating an efficient and low-loss ring-to-ring energy transfer. We show that energy…
Transient XUV spectroscopy is growing in popularity for the measurement of solar fuel and photovoltaic materials as it can separately measure electron and hole energies for multiple elements at once. However, interpretation of transient XUV…
Photoelectron emission from excited states of laser-dressed atomic helium is analyzed with respect to laser intensity-dependent excitation energy shifts and angular distributions. In the two-color XUV (exteme ultra\-violet) -- IR (infrared)…
Using extreme-ultraviolet attosecond-pulse-trains, we investigate the photoionization dynamics of a Helium atom in the presence of moderately-strong (~10^12 W/cm^2) femtosecond laser pulses. The electronic structure of a laser-dressed atom…
Linear polarization analysis of hard x-rays is employed to probe electronic anisotropies in metal-containing complexes with very high selectivity. We use the pronounced linear dichroism of nuclear resonant x-ray scattering to determine…
We investigate the photoionization spectrum of helium by attosecond XUV pulses both in the spectral region of doubly excited resonances as well as above the double ionization threshold. In order to probe for convergence, we compare three…
We employ few-femtosecond extreme ultraviolet (XUV) transient absorption spectroscopy to reveal simultaneously the intra- and interband carrier relaxation and the light-induced structural dynamics in nanoscale thin films of layered…
Optical orientation of carrier spins by circularly polarized light is the basis of spin physics in semiconductors. Here, we demonstrate strong optical orientation of 85\%, approaching the ultimate limit of unity, for excitons in…
Coherent optical spectroscopy such as four-wave mixing and photon echo generation deliver detailed information on the energy levels involved in optical transitions through the analysis of polarization of the coherent response. In…
Ionization with ultrashort pulses in the extreme ultraviolet (XUV) regime can be used to prepare an ion in a superposition of spin--orbit substates. In this work, we study the coherence properties of such a superposition, created by…
Chiral (highly helical) extreme ultraviolet (XUV) sources are pivotal for investigating chiroptical phenomena on the ultrafast electronic timescale. Table-top, coherent High Harmonic Generation (HHG)-based sources are particularly…
The development of spectroscopic techniques in the extreme ultraviolet (XUV) spectral range has significantly advanced the understanding of ultrafast interactions in magnetic systems triggered by optical excitation. In this work, we…
One of the challenges of excitonic materials is the accurate determination of the exciton binding energy and bandgap. The difficulty arises from the overlap of the discrete and continuous excitonic absorption at the band edge. Many…