Research News

Quasi-Symmetry reveals new topology

Symmetry is a key concept in our understanding of the physical world around us. They way self-similar components are arranged following the guidelines of symmetry dictates their joint behavior. It is no accident that the human body evolved in a mirror-symmetric shape, as beautifully captured by Da Vinci’s work. Similarly, in material science, certain symmetries dictate the functionality of a material on the quantum level. A recent focus point in the field is to understand how certain symmetries work together to give fundamentally new responses in so-called topological materials. These materials display distinct surface and bulk properties, making them promising candidates for future application in quantum electronics.
Ever since the discovery of the quantum Hall effect (Nobel Prize 1985), symmetry has been the guiding principle in the search for topological materials. Now an international team of researchers from Germany, Switzerland, and the USA has introduced an alternative guiding principle, ‘quasi-symmetry’, which leads to the discovery of a new type of topological material with great potential for applications in spintronics and quantum technologies. This work has been published in Nature Physics. more

A remote control for functional materials

Researchers in Hamburg have discovered that the ferroelectric polarization of lithium niobate (LiNbO3) changes in areas well away from the direct ‘hit’ of a laser pulse, with the polarization reversal occurring throughout the entire crystal. The team’s study of this hitherto unknown phenomenon - called nonlocal nonlinear phononics - has been published in Nature Physics. more

Easier interface for simulation tools

The use of simulation tools can be complicated and time-intensive. Now a research team from the MPSD and Imperial College London (UK) has developed a workflow that allows researchers to spend far less time on the syntax and data formats of the simulation package and to work with the data immediately. more

Ultrafast control of quantum materials

Research team involving experimentalists and theorists explores how light can fundamentally alter the properties of solids - and how to harness these phenomena in laser-driven materials for future applications. Their colloquium has been published in Reviews of Modern Physics. more

Simplified light-matter predictions

Predictions of how light interacts with real materials can consume vast computing resources. By reshaping the equation so that some quantum light is integrated in the matter component from the outset, scientists have developed a far more efficient approach. more

Twisted MoS<sub>2</sub> yields new exotic states

Twister bilayer MoS2 can be used to control kinetic energy scales in solids. Researchers have shown that the electrons in MoS2 can interfere destructively, stopping their motion for certain paths. Combined with the twist this makes it possible to engineer exotic magnetic states. more

Currents caused by laser loops

Theoreticians at the MPSD predict that a unique laser source could produce highly controllable electric currents in any bulk material. The team’s work has been published in PRL. more

Nematicity by magnetism in TBG

Researchers in Hamburg and Aachen suggest a surprising connection between the nematic behavior of a superconductor in a magnetic field — a state that resembles liquid crystals used in LCDs — and its spiral-like groundstate in the absence of the field. more

Trapped photons turn SrTiO<sub>3</sub> ferroelectric

Photons trapped in a cavity can cause a crystal known as Strontium Titanate (SrTiO3) to become ferroelectric, according to a new study by the MPSD’s Theory group. The findings have been published in PNAS. more

View of molecular motions in SEF

Researchers have watched in real time how molecules move during singlet exciton fission, an important process in light-based technologies. They observed the movements in single crystals comprised of pentacene molecules, showing that a collective motion of molecules may be the origin of the fast timescales connected to this process. more

Go to Editor View