One central aspect of live is, how does the brain work? Our brain allows fast recognition of complex patterns, and to analyze big data to reduce informations. This works by neuronal networks, that are self learning "We developed at Greifswald three dimsional patterns as scaffolds for neurons, realized by 3D laser lithography. The challange is to guide the axons by suface activation through 1–2 μm channels" explains Dr. Christian Denker. "If we further improve this way of producing guides neuronal structures that we can define at will, this will allow to simplify complex neuronal networks to study their function" says the collaborator Prof. Dr. Robert Blick at the Center for Hybrid Nanostructures CHyN, Hamburg.

Publication: Microscaffolds by Direct Laser Writing for Neurite Guidance Leading to Tailor‐Made Neuronal Networks, C. Fendler, et al. Advanced Biosystems (2019).

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In a collaboration between Universities of Uppsala, Konstanz, Kiel, Madrid and Western Digital, we lifted the mystery of all-optical manipulation of the magnetization of FePt recording media. Today, FePt nanograins are developed, because of their large magnetic anisotropy, resulting in a high thermal stability even for a few nanometer sized grains, arising in their high coercive field of more than 4 Tesla. They are currently developed further for heat assisted magnetic recording. Our collaboration showed that different steps are important, from ab-initio calculations of the light induced magnetization up to the correct thermal description of the spin ensemble. That shows again the complexity of ultrafast magnetization dynamics, and that there is no unique process for describing ultrafast magnetism. Our calculations for each grain entered into a simple rate model that can explain the switching statistics. To date multiple laser pulses are needed to get a decent writing success. With our single shot experiments compared to the calculations, we can make now predictions for the boundary condition for single-shot laser writing of magnetic bits in the future.  

Reference:

Magnetisation switching of FePt nanoparticle recording medium by femtosecond laser pulses

R. John, M. Berritta, D. Hinzke, C. Müller, T. Santos, H. Ulrichs, P. Nieves, J. Walowski, R. Mondal, O. Chubykalo-Fesenko, J. McCord, P. M. Oppeneer, U. Nowak, M. Münzenberg, Sci. Rep. 7, 4114 (2017). 

Terahertz waves offer numerous applications in ultrafast science. A a new concept for the generation of terahertz waves using spintronic materials can be realized.
In contrast to previous designs, the emitters consist of thin metal films and take advantage of the spin rather than only the charge of the electron. Following this approach, they developed broadband emitters fully covering the 1-to-30-THz range, while at the same time being simple designed and compact. Compact, because it is based on spin-orbit effects on femtosecond time scales converting the spin current into a THz emitting charge current on few nanometer lenght scales. 
Original article: 
T. Seifert et al., Efficient metallic spintronic emitters of ultrabroadband terahertz radiation, Nature Photonics 10, 483–488 (2016).

Nature Photonics

New equipment allows to fabricate three dimensional objects with a resolution of 150nm. As a test object we fabricated the dutch style drawbridge in the fisher village Wieck, a Greifswald local landmark (original on Wiki). The process works with pulsed laser writing by two-photon laser polymerization that allows to shrink the volume of writing a photoresist for pattering nano- and micron sized structures.

On TV, watch the contribution at the NDR news magazine: www.ndr.de