Investigating magnetic nano-chains

Chains of asymmetric nanodots were modelled, using micromagnetic simulations, to verify the possibility to introduce magnetic domain-walls. For this, a combination of an anisotropy, defining the direction in which the domain wall should move, with alternating magnetic fields of suitable frequency and amplitude was found to be necessary.

Controlling vortex circularity and polarity

Magnetic vortices are of high interest in basic and applied research, e.g. for possible applications in data storage, signal transfer, logic devices, etc. They can be described by the polarity of the central core (with the magnetization pointing "up" or "down") and their circularity (rotational direction of the magnetization around the central core). If it were possible to manipulate both properties independently, two bits could be realized by one such nano-dot with a vortex, similar to our approaches utilizing fourfold nanomagnets.

Electric field simulation for needle-electrospinning

Electrospinning can be used to create sub-micron fibers from diverse materials, from polymers to blends to ceramics. Electrospinning can be performed with two wires as electrodes, but most often a syringe is used to press the polymer solution (or melt) via a needle into the electric field where the material is stretched and drawn to a counter-electrode.

Possible hardware-based solutions leading to cognitive computing

The hardware emulation of stochastic invertible logic based on Arduino microcontrollers or implemented in magnetic tunnel junctions, the hardware belief networks, have been proposed recently by researchers from the School of Electrical and Computer Engineering, Purdue University (IN), USA. Importantly, the provided solutions realize not only standard stochastic computing of the Boolean type, but do it very precisely and in the invertible manner. The proposed computing network imitating synapses consists of elementary switches based on stochastic magnetic tunnel junctions.

Production parameters for carbon nanofibers

Polyacrylonitrile (PAN) is the most often used material for carbon fiber production. Carbon nanofibers, however, created from electrospun PAN nanofibers, necessitate different production parameters during stabilization and carbonization steps. Investigation of these parameters can be performed by various optical, chemical and other examinations, e.g. of the sample color (with increasing stabilization, samples get darker and darker), using FTIR, DSC, TGA, and other techniques.

Complexity and emergence of cognition

With the development of cognitive computing the next generation of future computing paradigms will be related to interesting issue of emergence of the new functionalities that results from increasing complexity of systems. The fundamental question is; at what level of complexity, and why at that level, a given functionality is accessible? And, an another specific question can be asked; is there the need to make observation in time or conclusion about the specific functionality can be extracted from the static, read at one moment, information?

Increasing biocompatibility of titanium bone implants

Bone implants are usually prepared from titanium which is biocompatible and highly resilient, but differs from bone tissue with respect to Young's modulus, resulting in possible scaffold loosening under stress. A porous geometry as well as the addition of growth factors can support adjusting the Young's modulus for an adapted scaffold-shaped geometry.

High symmetry gadolinium(III) polyhedra

In a recent article, creation of hollow nanospheres Gd20, Gd32, Gd50 and Gd60 is described using the approach to assemble fragments containing different polygons. While structural analysis revealed the symmetries of the respective nanospheres, magnetic studies show in theory and experiment that these polyhedra show antiferromagnetic interaction which can be attributed to classical spins at the Gd sites. Magnetic measurements can even be used as "fingerprints" to identify the polyhedra.