4D-STEM Nanoscale Strain Analysis in van der Waals Materials: Advancing beyond Planar Configurations

Achieving nanoscale strain fields mapping in intricate van der Waals (vdW) nanostructures, like twisted flakes and nanorods, presents several challenges due to their complex geometry, small size, and sensitivity limitations. Understanding these strain fields is pivotal as they significantly influence the optoelectronic properties of vdW...

The Bulk van der Waals Layered Magnet CrSBr is a Quasi-1D Material

Correlated quantum phenomena in one-dimensional (1D) systems that exhibit competing electronic and magnetic order are of strong interest for the study of fundamental interactions and excitations, such as Tomonaga-Luttinger liquids and topological orders and defects with properties completely different from the quasiparticles expected in their...

Charge Transfer and Asymmetric Coupling of MoSe₂ Valleys to the Magnetic Order of CrSBr

van der Waals heterostructures composed of two-dimensional (2D) transition metal dichalcogenides and vdW magnetic materials offer an intriguing platform to functionalize valley and excitonic properties in nonmagnetic TMDs. Here, we report magneto photoluminescence (PL) investigations of monolayer (ML) MoSe₂ on the layered A-type...

Highly Anisotropic Mechanical Response of the Van der Waals Magnet CrPS₄

Semiconducting van der Waals magnets exhibit a rich physical phenomenology with different collective excitations, as magnons or excitons, that can be coupled, thereby offering new opportunities for optoelectronic, spintronic, and magnonic devices. In contrast with the well-studied van der Waals magnets CrI₃ or Fe₃GeTe...

Sensing the Local Magnetic Environment through Optically Active Defects in a Layered Magnetic Semiconductor

Atomic-level defects in van der Waals (vdW) materials are essential building blocks for quantum technologies and quantum sensing applications. The layered magnetic semiconductor CrSBr is an outstanding candidate for exploring optically active defects because of a direct gap, in addition to a rich magnetic phase diagram, including a recently...

Integrating van der Waals materials on paper substrates for electrical and optical applications

Paper holds the promise to replace silicon substrates in applications like internet of things or disposable electronics that require ultra-low-cost electronic components and an environmentally friendly electronic waste management. In the last years, spurred by the abovementioned properties of paper as a substrate and the exceptional...

Effect of electrostatic interaction on the retention and remobilization of colloidal particles in porous media

We investigate the effect of pH on external hematite colloidal particles entrapment and remobilization by core-flood experiments combined with X ray computed tomography. Suspensions of calibrated hematite colloidal particles were injected into Bentheimer sandstones sample, composed mainly of well-sorted quartz and small clay fraction (up to 1...

Revisiting van der Waals Radii: From Comprehensive Structural Analysis to Knowledge-Based Classification of Interatomic Contacts

Weak noncovalent interactions are responsible for structure and properties of almost all supramolecular systems, such as nucleic acids, enzymes, and pharmaceutical crystals. However, the analysis of their significance and structural role is not straightforward and commonly requires model studies. Herein, we describe an efficient and universal...

Mobility and Recombination Dynamics of Charges in Low-Dimensional Van Der Waals Materials

This doctoral thesis reports studies on effects of temperature and density on the<br/>mobility and recombination dynamics of charge carriers in low-dimensional van<br/>der Waals materials.

Tree frog attachment: Mechanisms, challenges, and perspectives

Tree frogs have the remarkable ability to attach to smooth, rough, dry, and wet surfaces using their versatile toe pads. Tree frog attachment involves the secretion of mucus into the pad-substrate gap, requiring adaptations towards mucus drainage and pad lubrication. Here, we present an overview of tree frog attachment, with focus on (i) the...

First principles phase diagram calculation for the 2D TMD system WS₂−WTe₂

First principles phase diagram calculations, that included van der Waals interactions, were performed for the bulk transition metal dichalcogenide system (1−X)·WS₂−(X)·WTe₂. To obtain a converged phase diagram, a series of cluster expansion calculations were performed with increasing numbers of structural energies, (N...

Tip identification in atomic force microscopy using nonlinear dynamics

Since its invention, the Atomic Force Microscope has emerged into one of the most useful tools in<br/>nanotechnology due to its acclaimed abilities in exploring surface topography, micro- and nanoscale manipulation<br/>and characterization. The nonlinear interaction between the cantilever tip and the sample surface<br/>has been studied in great...

Nonlinear dynamics for estimating the tip radius in atomic force microscopy

The accuracy of measurements in Amplitude Modulation Atomic Force Microscopy (AFM) is directly related to the geometry of the tip. The AFM tip is characterized by its radius of curvature, which could suffer from alterations due to repetitive mechanical contact with the surface. An estimation of the tip change would allow the user to assess...

Multidimensionality in Fluidized Nanopowder Agglomerates

recent years, the interest in fluidization as a mean to process nanoparticles is strongly increasing. Due to the small size of the nanoparticles, which makes van der Waals forces predominate, they do not fluidize as single particles but as agglomerates. Various researchers using settling experiments and bed expansion measurements conclude that...

Understanding interactions between capped nanocrystals: Three-body and chain packing effects

Self-assembly of capped nanocrystals (NC) attracted a lot of attention over the past decade. Despite progress in manufacturing of NC superstructures, the current understanding of their mechanical and thermodynamic stability is still limited. For further applications, it is crucial to find the origin and the magnitude of the interactions that...

Molecular interpretation of nonclassical gas dynamics of dense vapors under the van der Waals model

The van der Waals polytropic gas model is used to investigate the role of attractive and repulsive intermolecular forces and the influence of molecular complexity on the possible nonclassical gas dynamic behavior of vapors near the liquid-vapor saturation curve. The decrease of the sound speed upon isothermal compression is due to the well-known...