Scientific Press Releases

Physicists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg have discovered a counterintuitive form of electronic transport. In microscopic devices carved from the semimetal bismuth, removing material does not reduce electrical conductance—as conventional wisdom would suggest—but can instead increase it. The study, published in Nature Physics and selected for the magazines cover, shows that when strong magnetic fields are applied to three-dimensional metals, electric currents can flow preferentially along the surfaces of the material known as chiral surface states. This finding sheds new light on the previously overlooked role of surface conduction in semimetals driven to the quantum limit. more

Scientists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) and an international team led by Pohang University of Science and Technology (POSTECH) have discovered that simply twisting two pieces of the crystal hexagonal boron nitride (hBN) against each other creates quantum wells that emit deep-ultraviolet light more than ten times more efficiently than the best existing semiconductor technology. First-principles calculations by MPSD theorists in Angel Rubio's department confirmed the underlying mechanism. The results are published in Science. more

The world is never really at rest. Even in a vacuum near ultracold temperatures where all classical motion should come to a halt, you will find quantum fluctuations. In thin, two-dimensional materials, these include random vibrations that can alter electromagnetic fields – a feature that theorists have long posited could be useful for modifying materials. Angel Rubio, Director of the Theory Department at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg, has been one of the principal architects of this idea. Together with colleagues Rubio developed the theoretical framework predicting that quantum fluctuations inside cavities could reshape the properties of solids – without any external force. Now, that prediction has been confirmed experimentally for the first time. In a new paper published in Nature, an international team of 33 researchers from 17 institutions – including a large MPSD contingent – demonstrates that quantum fluctuations from the vacuum alone inside atom-thin layers of a 2D material can alter the properties of a nearby crystal. more

Probing the vibration of atoms provides detailed information on local structure and bonding that define material properties. Tip-enhanced Raman spectroscopy (TERS) offers extremely high resolution to probe such vibrations. Krystof Brezina and Mariana Rossi from the MPI for the Structure and Dynamics of Matter (MPSD), and Yair Litman from the MPI for Polymer Research (MPIP), have demonstrated that realistic, first-principles simulations are essential for interpreting TERS images of molecules and materials on surfaces. Their approach reveals how interactions with metallic substrates reshape vibrational imaging at the nanoscale. The work has now been published in ACS Nano. more

Researchers at ETH Zurich and the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) have shown, for the first time with very high time and spatial resolution, that electrons in certain two-dimensional materials only follow the motion of the atomic nuclei with a delay. This insight could lead to the development of novel electronic devices in the future. more

Researchers at the Max-Planck-Institute for the Structure and Dynamics of Matter (MPSD) and partner institutes have developed a general and experimentally realistic method to create square-lattice moiré materials by twisting two-dimensional semiconductors with rectangular unit cells by 90 degrees. This simple geometric recipe produces moiré patterns with square symmetry and flat, isolated electronic bands that map onto a tunable square-lattice Hubbard model—the theoretical framework underpinning magnetism and high-temperature superconductivity. The approach works across a broad class of materials and offers powerful knobs to explore correlated-electron phases in a clean, gate-tunable platform. more

A joint team of scientists from Cornell University, Stanford University and the Max-Planck-Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg have shown that moiré patterns can move coherently when illuminated with light. Their study reveals ultrafast atomic twisting in 2D materials, overturning the existing view that light only causes random heating of the material. This work opens a new pathway for controlling electronic behavior with light in next-generation opto-electronic devices. This work has now been published in Nature. more

Physicists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg have discovered a striking new form of quantum behavior. In star-shaped Kagome crystals—named after a traditional Japanese bamboo-basket woven pattern—electrons that usually act like a noisy crowd suddenly synchronize, forming a collective “song” that evolves with the crystal’s shape. The study, published in Nature, reveals that geometry itself can tune quantum coherence, opening new possibilities to develop  materials where form defines function. more

Quantum materials are a fascinating platform for future technologies, as they host a variety of exotic phenomena beyond the reach of classical physics. Among them, van der Waals heterostructures stand out: They are created by stacking different two-dimensional layers that can be only one atom thick. These structures are remarkably easy to manipulate, offering unprecedented tunability and a vast realm for exploration. A team from the Max-Planck-Institute for the Structure and Dynamics of Matter (MPSD) and Columbia University has found that van der Waals heterostructures can naturally serve as cavities for long-wavelength terahertz (THz) light. This work has been published in Nature Physics. more

Ferroic materials, like ferromagnets and ferroelectrics, are central building blocks of modern data storage technology. Yet, current platforms face fundamental limits. Ferromagnets suffer from low switching speed, while the ferroelectric polarization is generally unstable because of the depolarizing response of the surrounding material. A newly discovered class of materials, which do not suffer from these limitations, are so-called ferroaxials. They are formed by microscopic vortices of electric dipoles that can either be arranged in a clockwise or anticlockwise texture, yet they are extremely difficult to manipulate. Researchers at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) and the University of Oxford have now shown that the bi-stable ferroaxial states can be switched on demand using single ultrashort flashes of circularly polarized terahertz light. This discovery establishes a new mechanism that may lead to light-controlled, ultrafast and stable ferroic switching, and a promising platform for next-generation non-volatile data storage technologies. more