Publication Spotlights

When characterizing hazardous materials such as toxic liquids, the less material you need for investigation, the better. This especially applies for harsh and extreme measurement conditions like high pressure or increased temperature. As described in their recent publication “Extreme thermodynamics ...

The research focus of Sebastian-Paul Kopp is laser-based 3D printing from polymer powders. As described earlier, he uses a technique similar to a common laser printer to individually deposit the powder onto the laser bed. In his subsequent work, he successfully adapted his setup to 3D-print custo...

In several recent publications, Lisa Ackermann reported her progress on laser beam shaping using spatial light modulators (SLMs). Now she adds another interesting piece of work as she was able to change the color of the shaped light in situ. In her publication “Polarization‑controlled nonlinear comp...

Not all metal is the same. Copper is known to be an excellent heat conductor, but on the other side a very soft and ductile material. Its strength and hardness is far away from the one of steel, which is an alloy of iron and carbon. However, the thermal conductivity of steel is more than an order of...

Last year, Sebastian-Paul Kopp introduced a new technique for powder deposition in laser-based additive manufacturing of polymer structures. He transferred charged polymer particles to the build platform using a locally charged photoconductive plate. This enables high powder efficiency and the print...

Last year, Markus Labus and Peter Lang published on their new setup for optical temperature measurements in flames and aerosols. They continued their efforts and now were able to demonstrate calibration-free imaging of temperature fields in flames containing indium particles. The fluorescent ligh...

Last year, Lisa Ackermann already published on beam shaping of high-energy lasers for materials processing by using spatial light modulators (SLMs). As she pointed out, a drawback is the presence of speckle noise, which overlays the shaped intensity structure and drastically reduces the beam quality...

A timeframe of 80 picoseconds is extremely short. In this interval, light rays – able to travel from the earth to the moon in about one second – go a distance of 2.5 millimeters only. In a joint project of Caltech, Gothenburg University, and FAU, Yogeshwar Nath Mishra and Florian Bauer now realized ...

As previously described, liquid organic hydrogen carrier (LOHC) fluids may play a major role in future energy storing, as they are able to reversibly store and release hydrogen molecules. This release, namely the dehydrogenation of the LOHC, is an endothermic reaction, which means it requires extern...

To safely store hydrogen as a future energy carrier, liquid organic hydrogen carrier (LOHC) systems are a highly promising option. In the presence of a catalyst, these organic molecules are able to repeatedly absorb and release hydrogen molecules through chemical reactions depending on the pressure ...

Last year, Florian Bauer published on his work on in-situ spectroscopy of soot formation. He continues his efforts in his recent publication on the “Characterisation of the transition type in optical band gap analysis of in-flame soot”. By monitoring the flame at two different positions, he uses abs...

The elasticity and flexibility of a human muscle and its contractile properties depend on the presence of reactive oxygen species as well as calcium ions. Mena Michael investigates the calcium responsiveness of muscles both during active contraction and passive stretching. He systematically assessed...

Bastian Lehnert works on the optimization of 3D imaging of transient fuel sprays. His measurement technique is called ‘diffuse back illumination extinction imaging’. Simply said, the fuel spray is placed between an LED panel with specific characteristics and a High-Speed-Camera which records the lig...

Earlier this year, Dominic Bartels published his work on in-situ modification of case-hardening steel. He continues these efforts in his recent work “PBF-LB/M of Low-Alloyed Steels: Bainite-like Microstructures despite High Cooling Rates”. It focusses on the processing of this group of steels using ...

Last year, Alexander Wittmann introduced a laser with a wavelength of 1.94 µm for the consolidation of thermoplastic polymer coatings on metallic substrates. Since light of this wavelength is absorbed in the polymers themselves, light-absorbing additives are not required for the coating process. Thi...

A promising approach to reconstruct human muscle tissue after trauma, necrosis or tumor ablation is the use of cell-free muscle scaffolds processed from previously intact donor organs. Up to now, the required chemical decellularization of tissues is performed mostly manually, with predefined incubat...

Duchenne Muscular Dystrophy, abbreviated as DMD, is a genetic muscular disease causing inflammations, reduced membrane stability and ongoing myatrophy. To understand and assess the causes and effects of this incurable disease, different mouse model systems are investigated for quite some time now. ...

Sebastian-Paul Kopp works on a new technique for powder deposition in laser-based additive manufacturing. Similar to the principle of a laser printer, a light-induced charge pattern on a photoconductive plate allows a spatially resolved distribution of polymer powder on the build platform. This redu...

Last year, Tim Russwurm showed that “Flame Luminesce in an Optically Accessible Engine with an Active Fuelled Pre-Chamber Ignition System” is a suitable detection technique for ignition and combustion processes. By monitoring the inside of an engine cylinder with a high speed camera he gained insigh...

To monitor the material’s topography in laser machining, optical coherence tomography (OCT) is a promising imaging technique, which goes beyond the state-of-the-art methods like laser triangulation. In his latest publication, Thomas Will identified relevant Features for image processing of OCT image...

In his latest publication, Florian Kordon presents a “Multi-Stage Platform for (Semi-)Automatic Planning in Reconstructive Orthopedic Surgery”. He developed a deep-learning algorithm for anatomical feature detection, which enables precise pre- and intra-operative surgery planning based on 2D X-ray i...

For her latest publication “Tailoring the Nature of Interface States in Efficient and Stable Bilayer Organic Solar Cells by a Transfer-Printing Technique”, Rong Wang developed a novel fabrication method, which enables solar cells containing two layers with a sharply defined planar interface. By regu...

Spray flame synthesis is a powerful tool for the generation of functionalized nanoparticles, yet sophisticated measurement techniques are required to investigate droplet evolution and nanoparticle formation in such a complex process. In his recent publication, “In Situ Determination of Droplet and N...

Laser-based additive manufacturing enables the realization of steel-based products in sophisticated new shapes. Dominic Bartels published on the “In situ modification of case-hardening steel 16MnCr5 by C and WC addition by means of powder bed fusion with laser beam of metals (PBF-LB/M)”. He investig...

For the first time, Manuel Kerscher determined the “Viscosity and Surface Tension of Benzene at Saturation Conditions from Surface Light Scattering”. His results consolidate the capability of surface light scattering as an accurate absolute measurement technique for the simultaneous determination of...

Thermoplastic foams are used in a broad variety of applications. The resulting foam properties are governed by the nucleation and bubble growth behavior, which are both strongly influenced by the thermophysical properties of the blowing-agent-loaded polymer melt. Especially knowledge on diffusion co...

Marc-Oliver Pleinert’s focus of research is the experimental validation of results emerging from quantum theory. By “Testing Higher-Order Quantum Interference with Many-Particle States”, he set a new benchmark in experimental studies of higher-order interference. He successfully observed two-particl...

Photovoltaic energy generation will play a major role in the future of producing electric energy. “Outdoor photoluminescence of large area photovoltaic modules”, investigated by Bernd Doll, can act as an on-site tool for fast and cost-effective characterization of solar cells. For investigation o...

Microcirculation describes the circulation of blood in the smallest vessels. The publication of Moritz Späth deals with the “Determination of the diameter of simulated human capillaries using shifted position‐diffuse reflectance imaging”. Using Monte-Carlo simulations, he showed that this non-invasi...

Recently, Stefan Richter published on “Imaging Trapped Ion Structures via Fluorescence Cross-Correlation Detection”. This highly sensitive technique yields structural information of the arrangement of single photon sources where direct imaging techniques fail. His results on the spatial frequenc...

With her “Arrangement for the benchmarking of in-situ process monitoring of topographical process signatures within the Laser Powder Bed Fusion process”, Karen Schwarzkopf presents a custom made setup for examination of defect mechanisms in additive manufacturing. This setup combines a low-cohere...

Rong Wang recently published on “Understanding the Microstructure Formation of Polymer Films by Spontaneous Solution Spreading Coating with a High-Throughput Engineering Platform”. She presents an automated workflow for the preparation and optical characterization of polymer films used in optoel...

In her publication “Utilizing the unique charge extraction properties of antimony tin oxide nanoparticles for efficient and stable organic photovoltaics”, Chao Liu presents a new and simple strategy in developing advanced interface materials for organic solar cells. By adding the metalloid antimo...

Albert These worked on the “Characterization of Aerosol Deposited Cesium Lead Tribromide Perovskite Films on Interdigited ITO Electrodes”. He showed that aerosol deposition can be used to fabricate semiconducting perovskite films at low cost. The devices showed good electrical transport properties ...

Recently, Alexander Wittmann published on the “Consolidation of thermoplastic coatings by means of a thulium-doped fiber laser”. He investigated the suitability of this laser for depositing polymer coatings on stainless steel substrates. To optimize the layer morphology, he varied the main proces...

With additive manufacturing, highly customized parts of high complexity and resolution can be fabricated. Mixing nanoparticles into the feedstock polymer powders may improve the outcome of the laser powder bed fusion. With a multitude of evaluation techniques, Alexander Sommereyns investigated the i...

The recent publication of Lisa Ackermann deals with “Uniform and efficient beam shaping for high-energy lasers”. By setting two spatial light modulators in a proper arrangement, she realized a setup that enables tailored light fields even for high-energy pulsed lasers. Thus, she was able to create a...

Thermal lensing is an unwanted effect in optics used for high-power laser imaging. The high light intensity causes a heat up of the lenses which induces a focus shift. To tackle this issue, Phillip Rall recently presented a “Simulation and compensation of thermal lensing in high-power optical system...

Yakun He successfully worked on “Unraveling the Charge-Carrier Dynamics from the Femtosecond to the Microsecond Time Scale in Double-Cable Polymer-Based Single-Component Organic Solar Cells”. She investigated the charge carrier dynamics of a representative polymer across seven orders of magnitude in...

In their latest publication “Doppler optical frequency domain reflectometry for remote fiber sensing”, Max Köppel and Jasper Podschus present a new method for fiber sensing. Using this technique, they were able to perform high-resolution distributed temperature measurements. To do so, optically ...

In their recent publication, Markus Labus and Peter Lang present “A versatile fibre-based setup for two-line atomic fluorescence thermometry in aerosol processes”.  They implemented a new kind of hexagonal close-packed burner for high precision temperature measurements of combustion processes. By...

The conference paper “Automatic Path Planning for Safe Guide Pin Insertion in PCL Reconstruction Surgery” by Florian Kordon presents a time-saving pathway to optimize drill positioning in ligament surgery. Therefore, anatomical features are extracted from X-ray images using deep learning techniqu...

Even nowadays, in the age of growing electromobility, the understanding of soot formation in combustion processes will remain import for many years to come. Florian Bauer’s “In situ characterization of absorbing species in stationary premixed flat flames using UV–Vis absorption spectroscopy” sho...

For his conference contribution “Determination of the beam position in laser deep penetration welding using coaxially acquired images of the keyhole front and machine learning”, Pablo Dilger trained a convolutional neural network in evaluation of high-speed images of laser welding processes. With hi...