Refine
Year of publication
Document Type
- Conference Proceeding (137)
- Article (104)
- Preprint (4)
- Part of a Book (3)
- Doctoral Thesis (2)
- Book (1)
- Habilitation (1)
- Other (1)
Institute
- Forschungszentrum Mikrotechnik (253) (remove)
Language
- English (247)
- German (5)
- Multiple languages (1)
Keywords
- Laser ablation (11)
- Y-branch splitter (11)
- arrayed waveguide gratings (11)
- photonics (8)
- integrated optics (6)
- Arrayed waveguide gratings (5)
- MMI splitter (5)
- OCT (5)
- insertion loss (5)
- AWG (4)
- AWG design (4)
- AWG-spectrometer (4)
- MMI splitters (4)
- Optical coherence tomography (4)
- silicon nitride (4)
- 3D MMI splitter (3)
- Couplers (3)
- Crosstalk (3)
- High-speed optical techniques (3)
- Micromechanical devices (3)
- Photonics (3)
- Telecommunications (3)
- frequency 100 GHz (3)
- polymers (3)
- transmission characteristics (3)
- wavelength division multiplexing (3)
- AWG-Analyzer tool (2)
- AWG-parameters tool (2)
- Dissolution rate monitor (2)
- Femtosecond laser (2)
- Gold (2)
- HEMT (2)
- IDA (2)
- Laser beam machining (2)
- Laser materials processing (2)
- Levodopa (2)
- Light propagation (2)
- MEMS (2)
- Measurement by laser beam (2)
- Microneedle (2)
- Nanogap sensor (2)
- Optical device fabrication (2)
- Optical fibers (2)
- Optical splitter (2)
- Parkinson’s disease (2)
- Polymer (2)
- Pump-probe microscopy (2)
- Redox cycling (2)
- Refractive index (2)
- Semiconductor device measurement (2)
- SiO2 (2)
- Silicon (2)
- Standards (2)
- Y-branch (2)
- arrayed waveguide grating (2)
- deep reactive ion etching (2)
- demultiplexing equipment (2)
- diamond (2)
- integrated photonics (2)
- laser ablation (2)
- optical beam splitters (2)
- optical communication equipment (2)
- optical properties (2)
- optical splitting (2)
- optical waveguides (2)
- pump-probe (2)
- rib waveguides (2)
- silicon compounds (2)
- telecommunication (2)
- telecommunications (2)
- thin film (2)
- #kinderuni4you (1)
- +NPC 372 (1)
- +TEJ 630 (1)
- 128-channel 10 GHz AWG design (1)
- 128-channel 10 GHz AWG simulation (1)
- 1x128 MMI splitter (1)
- 2768 Plasmasphere (1)
- 2784 Solar wind/magnetosphere interactions (1)
- 2x2 optical switch (1)
- 3D 1×4 Multimode Interference Splitter (1)
- 3D MMI splitters (1)
- 3D Y-branch splitter (1)
- 3D optical splitters (1)
- 3D splitter (1)
- AWG channel spacing (1)
- AWG design tool (1)
- AWG software tool (1)
- AWG transmission parameters (1)
- AWG-Parameters (1)
- AWG-Spectrometer (1)
- AWG-based demultiplexers (1)
- AWG-parameter layout (1)
- AWG-parameter tool (1)
- AZ MiR 701 (1)
- Ablation efficiency (1)
- Active alignment (1)
- Adaptive optics (1)
- AlGaN-GaN (1)
- AlGaN/GaN HEMT (1)
- Aluminum gallium nitride (1)
- Apollo photonics (1)
- Automated Adjustment (1)
- Biodegradable polymers (1)
- Biosensor (1)
- Biosensors (1)
- Bulk micromachining (1)
- Burst mode (1)
- CMOS-Compatible (1)
- CRESS satellite (1)
- Channel spacing (1)
- Characterization (1)
- Chemical sensors (1)
- Children university (1)
- Chronoamperometry (1)
- Color (1)
- Computational fluid dynamics (1)
- Conduction bands (1)
- Copper (1)
- Coupling of Fiber Array (1)
- Coupling structure (1)
- Covid-19 crisis (1)
- Cracking (1)
- Cycle-olefin polymer (COP) (1)
- DLW (1)
- DRM (1)
- DWDM (1)
- Dental hard tissue ablation (1)
- Diodes (1)
- Distributed feedback lasers (1)
- Dye lasers (1)
- EBDW lithography (1)
- Electric potential (1)
- Electrochemical biosensor (1)
- Electrochemical detection (1)
- Electrodes (1)
- Elemental semiconductors (1)
- Enamel (1)
- Entangled photons (1)
- Excimer lasers (1)
- Excited States (1)
- FTTx (1)
- FTTx networks (1)
- Femtosecond ablation (1)
- Femtosecond phenomena (1)
- Fiber arrays (1)
- Fibre array (1)
- Fine-structure splitting (1)
- Fingers (1)
- Fs-laser ablation (1)
- GPON access networks (1)
- GaAs (1)
- GaN-SiC (1)
- Gallium nitride (1)
- Gas sensor (1)
- Hot States (1)
- Hot embossing (1)
- ICP (1)
- III-V semiconductors (1)
- IP-Dip polymer (1)
- Industry (1)
- Interdigitated electrode array (1)
- Interdigitated electrode array (IDA) (1)
- Irradiated tissue (1)
- LED (1)
- LIPPS (1)
- LSMO membrane (1)
- Lab-on-a-Chip (1)
- Lab-on-a-chip (1)
- Lab-on-a-chip (LOC) (1)
- Laser (1)
- Laser dicing (1)
- Layout (1)
- Light (1)
- Light's got it! (1)
- Lithography (1)
- Lithography simulation (1)
- Log-periodic antenna (1)
- Loss measurement (1)
- MEMS sensors (1)
- MMI (1)
- MMI Splitter (1)
- Mask aligner (1)
- Mask-Aligner (1)
- Mask-Aligner lithography simulation (1)
- Materialbearbeitung, Metallbearbeitung (1)
- Materials (1)
- Microbolometer (1)
- Micromachining (1)
- Microsphere lithography (1)
- Monitoring (1)
- Multimode interferece (1)
- Nanogap (1)
- Nickel (1)
- Noise measurement (1)
- OCT on-chip (1)
- OCT-spectrometer (1)
- Optical coupling (1)
- Optical crosstalk (1)
- Optical fiber sensors (1)
- Optical lithography (1)
- Optical losses (1)
- Optical measurements (1)
- Optical performance (1)
- Optical polarization (1)
- Optical properties (1)
- Optical refraction (1)
- Optical transmission systems (1)
- Optiwave photonic tool (1)
- Optiwave software tool (1)
- PICs (1)
- PON (1)
- Painless treatment (1)
- Passivation (1)
- Phosphor sheets (1)
- Photonic crystal (1)
- Photonics Explorer (1)
- Photonics integrated circuit (1)
- Photoresist (1)
- Photoresist calibration (1)
- Physics - Optics (1)
- Picosecond laser ablation (1)
- Picosecond-neodymium-vanadate laser (1)
- Polycrystalline diamond (1)
- Polymer AWG (1)
- Polymer based optical splitters (1)
- Propagation losses (1)
- Protocols (1)
- Proximity printing (1)
- Quantum Dots (1)
- Quantum Optics (1)
- Quantum dot lasers (1)
- Quantum dots (1)
- Quantum state tomography (1)
- R-soft photonic tool (1)
- Resists (1)
- S-Bend (1)
- SPR 955-CM (1)
- Scanning electron microscopy (1)
- Schottky diodes (1)
- Second harmonic generation (1)
- Second harmonic seeding (1)
- Semiconducting metal oxide (1)
- Semiconductor lasers (1)
- Semiconductor quantum dots (1)
- Sensing applications (1)
- Sensitivity (1)
- Sensor (1)
- Sensors (1)
- Shape (1)
- Si3N4 (1)
- Si3N4 based AWG spectrometer (1)
- Si3N4 based AWGs (1)
- Si3N4 waveguides (1)
- SiC MEMS (1)
- SiC substrates (1)
- SiN Photonics (1)
- SiN passive optical components (1)
- SiNx thin films (1)
- Silicon carbide (1)
- Simultaneous irradiation (1)
- Spectral multiplex (1)
- Splitter design (1)
- SrTiO3 single crystals (1)
- Steel (1)
- Strain tuning (1)
- Substrates (1)
- Subwavelength structures (1)
- Surface roughness (1)
- Surfaces (1)
- TM-polarized light (1)
- Telekommunikation (1)
- Temperature (1)
- Temperature Dependency (1)
- Temperature characterization (1)
- Temperature measurement (1)
- Temperature stability (1)
- Terahertz radiation (1)
- Two color excitation (1)
- UV laser ablation (1)
- Ultra-Dense WDM (1)
- Ultra-short pulse laser (1)
- Ultrashort laser pulses (1)
- Ultrashort pulses microfabrication (1)
- WDM-PON system (1)
- Waveguide photonic building blocks s (1)
- Wavelength measurement (1)
- Wet etching (1)
- X-rays (1)
- XG-PON access networks (1)
- Y-branch optical splitter (1)
- Y-branch waveguide shape modelling (1)
- ablation (1)
- absorption spectra (1)
- access network (1)
- active magnetic bearings (1)
- alignment marks (1)
- aluminium compounds (1)
- asymmetric splitting ratio (1)
- autonomous vehicle (1)
- background noise (1)
- backside damaging (1)
- beam propagation method (1)
- bubble detection (1)
- bubble dynamics (1)
- carbon (1)
- carbon allotropes (1)
- carbon nanotubes (1)
- colourless 8-channel AWG (1)
- colourless AWG (1)
- commercial photonics software tool (1)
- commercial photonics tools (1)
- concept (1)
- configurations (1)
- confined ablation (1)
- confined laser ablation (1)
- cyclic AWG (1)
- design (1)
- design and simulation (1)
- direct laser writing lithography (1)
- dual plasma (1)
- dynamics (1)
- e-beam lithography (1)
- elastic constants (1)
- electrochemical biosensor (1)
- electron beam lithography (1)
- electron-beam direct-write (1)
- epitaxial heterostructures (1)
- femtosecond laser ablation (1)
- femtosecond laser ablation technique (1)
- femtosecond laser processing (1)
- femtosecond-laser (1)
- fiber array (1)
- frequency 10 GHz (1)
- friction (1)
- gallium compounds (1)
- gas sensing (1)
- geomagnetic activity (1)
- greenhouse (1)
- hard tissue (1)
- harsh environment (1)
- high channel Y-branch splitter (1)
- high channel count AWG (1)
- high electron mobility transistors (1)
- high index contrast AWG (1)
- high-index contrast AWG (1)
- information and communication technology (1)
- laser microtexturing (1)
- laser writing optical lithography (1)
- lift-off free (1)
- light polarisation (1)
- light propagation (1)
- light transmission (1)
- low loss 1×64 y-branch splitter (1)
- low-index 8-channel optical demultiplexer (1)
- material optimization (1)
- mechatronics (1)
- medical diagnostic imaging applications (1)
- metal (1)
- microelectromechanical systems (1)
- micromechanic structures fabrication (1)
- microscopy (1)
- microsensors (1)
- miniaturization (1)
- modelling (1)
- multimode interference splitter (1)
- multiplexing equipment (1)
- nanogap (1)
- nanostructures (1)
- narrow channel spacing AWG (1)
- nonlinear dynamics (1)
- oa (1)
- optical coherence tomography (1)
- optical communication systems (1)
- optical datatransmissison (1)
- optical design (1)
- optical design techniques (1)
- optical fibre losses (1)
- optical fibre networks (1)
- optical gas sensors (1)
- optical multiplexers//demultiplexers (1)
- optical noise (1)
- optical power splitter (1)
- optical splitters (1)
- optical switch (1)
- optical transmission systems (1)
- optimisation (1)
- packaging (1)
- parametric excitation (1)
- passive optical networks (1)
- photolithography (1)
- photonic integrated circuit (1)
- photonic integrated circuits (1)
- photonics chip butt coupling (1)
- photonics integrated circuit (1)
- photonics integrated circuits (1)
- plasmapause (1)
- polarization dependent loss. (1)
- polymer (1)
- power splitter (1)
- process monitoring (1)
- redox cycling (1)
- rib waveguide (1)
- ridge waveguide (1)
- ridge waveguides (1)
- rotor dynamics (1)
- rotordynamics (1)
- sensor (1)
- silica based AWG designs (1)
- silicon laser ablation (1)
- simulated transmission characteristics (1)
- small footprint (1)
- solar wind (1)
- spectral domain OCT (1)
- split power (1)
- splitter (1)
- splitting properties (1)
- sputter etching (1)
- stand-alone software tool (1)
- surface characterization (1)
- symmetric splitting ratio (1)
- temperature sensitivity of parameters (1)
- tool design (1)
- tribological characterization (1)
- two-dimensional morphology (1)
- two-temperature model (1)
- ultra-DWDM (1)
- ultra-dense wavelength division multiplexing (1)
- ultra-short pulsed laser (1)
- ultrafast laser (1)
- ultrashort pulse laser (1)
- waveguide structure (1)
- waveguide tapers (1)
- waveguides (1)
- wavelength 850 nm (1)
- wear (1)
- wide band gap semiconductors (1)
X-ray microtomography is a nondestructive, three-dimensional inspection technique applied across a vast range of fields and disciplines, ranging from research to industrial, encompassing engineering, biology, and medical research. Phasecontrast imaging extends the domain of application of x-ray microtomography to classes of samples that exhibit weak attenuation, thus appearing with poor contrast in standard x-ray imaging. Notable examples are low-atomic-number materials, like carbon-fiber composites, soft matter, and biological soft tissues.We report on a compact and cost-effective system for x-ray phase-contrast microtomography. The system features high sensitivity to phase gradients and high resolution, requires a low-power sealed x-ray tube, a single optical element, and fits in a small footprint. It is compatible with standard x-ray detector technologies: in our experiments, we have observed that single-photon counting offered higher angular sensitivity, whereas flat panels provided a larger field of view. The system is benchmarked against knownmaterial phantoms, and its potential for soft-tissue three-dimensional imaging is demonstrated on small-animal organs: a piglet esophagus and a rat heart.We believe that the simplicity of the setupwe are proposing, combined with its robustness and sensitivity, will facilitate accessing quantitative x-ray phase-contrast microtomography as a research tool across disciplines, including tissue engineering, materials science, and nondestructive testing in general.
In this paper, low-loss Y-branch splitters up to 128 splitting ratio are designed, simulated, and optimized by using 2D beam propagation method in OptiBPM tool by Optiwave. For an optical waveguide, a silica-on-silicon material platform is used. The splitters were designed as a planar structure for a telecommunication operating wavelength of 1.55 m. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. The influence of the pre-defined S-Bend waveguide shapes (Arc, Cosine, Sine) and of the waveguide core size reduction on the splitter performance has been also studied. The obtained simulation results of all designed splitters with different S-Bend shape waveguides together with the different waveguide core sizes are discussed and compared with each other.
We have investigated the ablation behaviour of single crystal SrTiO3 <100> with focus on the influence of the pulse duration at a wavelength of 248 nm. The experiments were performed with KrF-excimer lasers with pulse durations of 34 ns and 500 fs, respectively. Femtosecond-ablation turns out to be more efficient by one order of magnitude and to eliminate the known problem of cracking of SrTiO3 during laser machining with longer pulses. In addition, the cavities ablated with femtosecond pulses display a smoother surface with no indication of melting and well-defined, sharp edges. These effects can be explained by the reduced thermal shock effect on the material by using ultrashort pulses.
In recent years, ultrashort pulsed lasers have increased their applicability for industrial requirements, as reliable femtosecond and picosecond laser sources with high output power are available on the market. Compared to conventional laser sources, high quality processing of a large number of material classes with different mechanical and optical properties is possible. In the field of laser cutting, these properties enable the cutting of multilayer substrates with changing material properties. In this work, the femtosecond laser cutting of phosphor sheets is demonstrated. The substrate contains a 230 micrometer thick silicone layer filled with phosphor, which is embedded between two glass plates. Due to the softness and thermal sensitivity of the silicone layer in combination with the hard and brittle dielectric material, the separation of such a material combination is challenging for both mechanical separation processes and cutting with conventional laser sources. In our work, we show that the femtosecond laser is suitable to cut the substrate with a high cutting edge quality. In addition to the experimental results of the laser dicing process, we present a universal model that allows predicting the final cutting edge geometry of a multilayer substrate.
Ultrafast-laser manufacture of radially emitting optical fiber diffusers for medical applications
(2018)
Transparent laser-structured glasses with superhydrophilic properties for anti-fogging applications
(2019)
Ultrashort pulse laser structuring enables direct modification of glass surfaces to generate superhydrophilic properties for anti-fogging applications. This approach makes coatings dispensable and the generated surfaces remain thermally, mechanically, and chemically resistant. However, the laser-generated structures usually cause scattering, which decreases transmission and may disturb the vision through the modified glass in the dry state. The aim of this study was to find a laser-processing strategy to achieve superhydrophilic, anti-fogging properties on glass surfaces with maximum transmission and minimal visual perception of the generated structure. For this purpose, we used an ultrashort-pulsed laser to generate periodic patterns of rippled circles or rough holes with varying pitch. The water contact angle and transmission of the structured glasses were measured as a function of the structured area. It was found that a periodic pattern of holes, which covers less than 1% of the surface, is already sufficient to reach the superhydrophilic state (contact angle < 5°) and provides nearly the same transmission as pristine glass. Pictures of objects imaged through dry, structured glasses, which were placed close to the lens or object, showed in both cases only a minimal decrease of contrast. If this minor drawback can be accepted, this direct laser structuring approach could be an interesting alternative to coating-based techniques and leaves even room to apply additional coatings for the fabrication of multi-functional special glasses.