An international team of researchers has found at the free electron laser FLASH a surprising effect that leads in ferromagnetic materials to a spatially varying magnetization manipulation on an ultrafast timescale.
Magnetic force microscopy image of a 10µm X 10µm sized sample showing a labyrinth-type magnetic domain structure. The magnetization is oriented perpendicularly to the surface (white: magnetization pointing out of the plane; brown: magnetization pointing into the plane).
photo/©: Bastian Pfau, TU Berlin
At the FLASH free electron laser at the DESY Research Center in Hamburg, results were obtained that are in agreement with a recently theoretically predicted mechanism: due to the laser pulses, highly excited electrons are generated that move quickly through the material. They thus move from one domain into a neighboring domain with a different magnetization direction. Since the electrons carry part of the magnetization, they manipulate the magnetization in the domains as they move across a domain wall. This means that domain walls can change their geometry on the fs time scale.
As domain walls are also used in memory devices, such as the racetrack memory, these investigations could be the first step to improving the performance of such devices. The racetrack memory is a development by IBM and could in the future be a fast and low power alternative to conventional random access memory or hard drives.The experiments were carried out by the researchers from Johannes Gutenberg University Mainz (JGU) with colleagues from TU Berlin, the universities of Hamburg and Paris, and six further research institutes at the free electron laser FLASH at DESY in Hamburg. The samples investigated consist of a cobalt-platinum multilayer system, which forms labyrinth-type domain structures.
Petra Giegerich | idw
Melting solid below the freezing point
23.01.2017 | Carnegie Institution for Science
An innovative high-performance material: biofibers made from green lacewing silk
20.01.2017 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
23.01.2017 | Health and Medicine
23.01.2017 | Physics and Astronomy
23.01.2017 | Process Engineering