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Surprise in solid-state physics: The Hall effect, which normally requires magnetic fields, can also be generated in a completely different way - with extreme strength. Electric current is deflected by a magnetic field - in conducting materials this leads to the so-called Hall effect. This effect is often used to measure magnetic fields.

Quantum technologies for computers open up new concepts of preserving the privacy of input and output data of a computation. Scientists from the University of Vienna, the Singapore University of Technology and Design and the Polytechnic University of Milan have shown that optical quantum systems are not only particularly suitable for some quantum computations, but can also effectively encrypt the associated input and output data.

Noise limits the performance of modern quantum technologies. However, particles traveling in a superposition of paths can bypass noise in communication. A collaboration between the Universities of Hong-Kong, Grenoble and Vienna, as well as the Austrian Academy of Sciences, under the lead of Philip Walther, reveals novel techniques to reduce noise in quantum communication.

Microstructure and macroscopic electro-mechanical properties are closely coupled in so-called ferroelectric polymers. An explanation for the high temperature dependence of this coupling has now been found at TU Wien. In certain materials, electrical and mechanical effects are closely linked: for example, the material may change its shape when an electrical field is applied or, conversely, an electrical field may be created when the material is deformed.

How do you measure objects that you can't see under normal circumstances? Utrecht University and TU Wien (Vienna) open up new possibilities with special light waves. Laser beams can be used to precisely measure an object's position or velocity. Normally, however, a clear, unobstructed view of this object is required - and this prerequisite is not always satisfied.

For years, the metal nanoparticles used in catalysts have been getting smaller and smaller. Now, a research team at TU Wien in Vienna, Austria have shown that everything is suddenly different when you arrive at the smallest possible size: a single atom. Metals such as gold or platinum are often used as catalysts.

Why do metal oxide surfaces behave differently? At TU Wien, a new research method was found to answer important questions. Metal surfaces play a role as catalysts for many important applications - from fuel cells to the purification of car exhaust gases. However, their behaviour is decisively affected by oxygen atoms incorporated into the surface.

When T-cells of our immune system become active, tiny traction forces at the molecular level play an important role. They have now been studied at TU Wien. Highly complicated processes constantly take place in our body to keep pathogens in check: The T-cells of our immune system are busy searching for antigens - suspicious molecules that fit exactly into certain receptors of the T-cells like a key into a lock.

A wide array of technologies, ranging from lasers and optical telecommunication to quantum computing rely on nonlinear optical interaction. Typically, these nonlinear interactions, which allow a beam of light, for example, to change its frequency, are implemented by bulk materials. In a new study an international research team led by the University of Vienna have shown that structures built around a single layer of graphene allow for strong optical nonlinearities that can convert light.

The Unruh-effect connects quantum theory and relativity. Until now, it could not be measured. A new idea could change this - in a completely different way than ever before. Is the vaccum really empty? Not necessarily. This is one of the strange results obtained by connecting quantum theory and the theory of relativity: The Unruh effect suggests that if you fly through a quantum vacuum with extreme acceleration, the vacuum no longer looks like a vacuum: rather, it looks like a warm bath full of particles.

Crucial new technologies such as hydrogen production or carbon capture require new catalysts. Experiments show: It's not just the material that matters, but also its atomic surface structure. On the way to a CO2-neutral economy, we need to perfect a whole range of technologies - including the electrochemical extraction of hydrogen from water, fuel cells, or carbon capture.

Infrared light can be used to detect molecules - but it is hard to create strong, short laser pulses. A new solution was found at TU Wien. Ordinary solid-state lasers, as used in laser pointers, generate light in the visible range. For many applications, however, such as the detection of molecules, radiation in the mid-infrared range is needed.

For years, physicists at TU Wien have been studying strange phenomena - now they have found an explanation that could help to understand unconventional types of superconductivity. Materials can assume completely different properties - depending on temperature, pressure, electrical voltage or other physical quantities.

A human research team and a machine learning algorithm have found that we need to rethink much of what we know about iridium oxide.

"During its expansion, the universe evolved towards its present state, which is homogeneous and isotropic on large scales. This is inferred, among other things, from the measurement of the so-called background radiation as nicely seen in the full sky image of the WMAP data.

Electrochemical reactions, which will play an important role in the future of energy supply, can now be explained in detail, thanks to measurements carried out by TU Wien and DESY. 1/4 images The elektrochemistry team at TU Wien: Andreas Nenning, Harald Summerer, Alexander Opitz (left to right) (Copyright: TU Wien) 1/4 images The elektrochemistry team at TU Wien: Andreas Nenning, Harald Summerer, Alexander Opitz (left to right) (Copyright: TU Wien) 1/4 images A Perovskite thin film electrode, on a ZrO2 crystal - compared to a pen.

In a very unusual way, the electrical and magnetic properties of a particular crystal are linked together - the phenomenon was discovered and explained at TU Wien (Vienna). Electricity and magnetism are closely related: Power lines generate a magnetic field, rotating magnets in a generator produce electricity.

Why do different measurements of material properties sometimes give different results? A research team led by the TU Vienna has now found an important answer. It is very hard to take a photo of a hummingbird flapping its wings 50 times per second. The exposure time has to be much shorter than the characteristic time scale of the wing beat, otherwise you will only see a colorful blur.

International research team describes the new possibilities offered by the use of ultracold dipolar atoms The quantum properties underlying crystal formation can be replicated and investigated with the help of ultracold atoms. A team led by Dr. Axel U. J. Lode from the University of Freiburg's Institute of Physics has now described in the journal Physical Review Letters how the use of dipolar atoms enables even the realization and precise measurement of structures that have not yet been observed in any material.

By Christoph Pelzl Simulations at Graz University of Technology refute earlier theories on long-range charge transfer between organic and inorganic materials. Oliver Hofmann and his research group at the Institute of Solid State Physics at TU Graz are working on the optimization of modern electronics.