Department News

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

Andrea Cavalleri, founding director of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD), will be awarded the Stern-Gerlach-Medal of the German Physical Society (DPG). He receives the Prize in recognition of his “pioneering work in light-based control of quantum materials, with which he made groundbreaking contributions to controlling emergent phenomena in solid-state 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

Mohammad Hafezi, Professor at the University of Maryland and Fellow of the Joint Quantum Institute (JQI), has been honored with a Humboldt Research Award. As part of the award, he will spend time at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg, collaborating with leading scientists in the field of quantum materials and light-matter interactions. more

Researchers at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) have developed an innovative method to study ultrafast magnetism in materials. They have shown the generation and application of magnetic field steps, in which a magnetic field is turned on in a matter of picoseconds. more