Multiphoton ionization of potassium atoms with a sequence of two counter-rotating circularly polarized femtosecond laser pulses produces vortex-shaped photoelectron momentum distributions in the polarization plane describing Archimedean spirals. The pulse sequences are produced by polarization shaping and the three-dimensional photoelectron distributions are tomographically reconstructed from velocity map imaging measurements. We show that perturbative ionization leads to electron vortices with c_{6} rotational symmetry. A change from c_{6} to c_{4} rotational symmetry of the vortices is demonstrated for nonperturbative interaction.

Bichromatic polarization-shaped femtosecond laser pulses are used to control three-dimensional photoelectron momentum distributions (3D-EDs) from resonance enhanced multi-photon ionization of potassium atoms. The light fields consisting of two spectral bands with different ellipticity are produced using an ultrafast polarization pulse shaper equipped with a custom polarizer in the Fourier plane. The tomographically reconstructed 3D-EDs from ionization with counterrotating circularly or orthogonal linearly polarized bichromatic laser pulses show different angular momentum superposition states at four distinct photoelectron energies. The analysis of the measured 3D-EDs reveals that the underlying physical mechanism is based on the interplay of ionization pathway selection via quantum mechanical selection rules for optical transitions and intrapulse frequency mixing of the spectral bands with different ellipticity. multiple ionization pathways by energetic separation of different angular momentum target states. Control of the ionization pathway along with energy-and angle-resolved detection allows us, on the one hand, to generate individual angular momentum free electron wave packets using CNR-CP bichromatic pulses and, on the other hand, to create unusual angular momentum superposition states using O-LP bichromatic pulses. In the experiment, bichromatic polarization-tailored fields are produced using a f 4 polarization pulse shaper [35] equipped with a custom polarizer in the Fourier plane [36,37]. Multiple photoelectron momentum images are recorded employing a velocity map imaging (VMI) spectrometer [38] and subsequently combined to reconstruct the 3D-EDs using a tomography algorithm [39][40][41]. Positive and negative time delays between the two colors are introduced to discriminate resonant from non-resonant ionization and to observe signatures from spin-orbit wave packets (SOWPs) in the 3D-EDs. A similar setup was recently used to produce electron vortices with a sequence of two one-color CNR-CP femtosecond laser pulses [42]. In that experiment, the minimal time delay in the sequence was given by the pulse length in order to avoid the creation of linear polarization in the overlapping interval. However, CNR-CP bichromatic fields, consisting of temporally overlapping left-(L-CP) and right-handed circularly (R-CP) polarized disjoined spectral bands do not create linearly polarized light. This feature allows us to observe photoelectrons from REMPI by overlapping bichromatic CNR-CP pulses such that frequency mixing between photons of opposite helicity can occur. For example, we demonstrate that 3D-EDs from three-photon ionization with two red L-CP photons and one blue R-CP photon are observed in a specific kinetic energy window.We start in section 2 with a theoretical discussion of the 3D-EDs from 1+2 REMPI with bichromatic polarization-shaped laser pulses. Section 3 introduces the experimental strategy based on the combination of polarization pulse shaping and tomographic photoelectron imaging. The experimental ...

Automated vehicles promise transformational benefits for future mobility systems, but only if they will be used regularly. However, due to the associated loss of control and fundamental change of in-vehicle user experience (shifting from active driver to passive passenger experience), many humans have reservations toward driving automation, which question their sufficient usage and market penetration. These reservations vary based on individual characteristics such as initial attitudes. User-adaptive in-vehicle Human-Machine Interfaces (HMIs) meeting varying user requirements may represent an important component of higher-level automated vehicles providing a pleasant and trustworthy passenger experience despite these barriers. In a driving simulator study, we evaluated the effects of two HMI versions (with permanent vs. context-adaptive information availability) on the passenger experience (perceived safety, understanding of driving behavior, driving comfort, driving enjoyment) and trust in automated vehicles of 50 first-time users with varying initial trust (lower vs. higher trust group). Additionally, we compared the user experience of both HMIs. Presenting driving-related information via HMI during driving improved all assessed aspects of passenger experience and trust. The higher trust group experienced automated driving as safest, most understandable and most comfortable with the context-adaptive HMI, while the lower trust group tended to experience the highest safety, understanding and comfort with the permanent HMI. Both HMIs received positive user experience ratings. The context-adaptive HMI received generally more positive ratings, even though this preference was more pronounced for the higher trust group. The results demonstrate the potential of increasing the system transparency of higher-level automated vehicles through HMIs to enhance users’ passenger experience and trust. They also consolidate previous findings on varying user requirements based on individual characteristics. User group-specific HMI effects on passenger experience support the relevance of user-adaptive HMI concepts addressing varying needs of different users by customizing HMI features, such as information availability. Consequently, providing full information permanently cannot be recommended as a universal standard for HMIs in automated vehicles. These insights represent next steps toward a pleasant and trustworthy passenger experience in higher-level automated vehicles for everyone, and support their market acceptance and thus the realization of their expected benefits for future mobility and society.

Incidents such as pollution or smuggling occur regularly at sea. These incidents needto be investigated by the responsible authorities in order to minimise consequentialdamage and prosecute those responsible. However, the current procedures used byinvestigators are very ineffective. That is why we have developed a software toolcalled Smart Profiling Engine (SPE). This tool supports investigators in their workand should lead to greater efficiency. In this paper, we present both the tool and astudy design that we will use to evaluate its efficiency compared to the traditionalinvestigation method.

This paper gives an overview of the results of the German national project AutoAkzept. The objective of the project was to develop solutions for the design of automated vehicles that promote the development of trust and thus acceptance for connected, cooperative, and automated mobility by reducing or even preventing subjective uncertainties and associated negative experiences. To this end, AutoAkzept developed technological building blocks for the assessment of activities and states of users of automated vehicles, the creation and application of individual user profiles for the optimization of system adaptation to users as well as strategies for adapting the behavior of automated vehicles in terms of information transfer, interior set-up, routing, and driving style selection. In developing these solutions, the project focused on the essential needs of users of automated systems. These needs should be considered in the conception and design of automated vehicles as well as in their operational use.