Highlights

Controlling how fast quantum systems relax toward their steady state is a central challenge for quantum simulation and state preparation, especially in the presence of dissipation. In a joint effort between the Biological Physics and Condensed Matter divisions of the Max Planck Institute for the Physics of Complex Systems, Nicolò Beato and Gianluca Teza have now introduced a general strategy to tune relaxation dynamics in open quantum systems.
Their approach is inspired by ideas related to the Mpemba effect—the counterintuitive observation that hot water can sometimes freeze faster than cold. Extending this concept to the quantum realm, the authors show that relaxation can be dramatically altered by preparing the system in a carefully chosen initial state. By applying a single unitary transformation, the method selectively suppresses specific dissipative modes that would otherwise slow down (or speed up) the dynamics. Unlike conventional control protocols, this strategy requires no active intervention during the evolution itself and remains effective even in systems with dense and complex relaxation spectra.
By enabling both acceleration and prolongation of relaxation under realistic constraints, this work opens new avenues for controlling nonequilibrium quantum dynamics in modern quantum simulators.

Figure: A unitary transformation acts as a spectral filter for dissipation in an open quantum system. By selectively redirecting slow relaxation modes while preserving the steady state, the transformation reshapes the relaxation dynamics without requiring active control during evolution, enabling precise tuning even in the presence of dense dissipative spectra.

Nicoló Beato and Gianluca Teza, Phys. Rev. Lett. 136, 070401 (2026)

Nearly three centuries ago, Euler explained how an elastic line buckles under compression in the plane. This classical, minimal calculation epitomises mechanical bifurcations.
Shiheng Zhao and Pierre Haas of the Max Planck Institute for the Physics of Complex Systems and the Max Planck Institute of Molecular Cell Biology and Genetics have now answered the question that Euler did not solve: How does such a compressed line buckle within a curved surface? Combining exact and numerical calculations, the researchers discovered that the mathematical bifurcation structure changes fundamentally. In particular, there can be a surprising "snap-through" instability at larger compressions, whereby the elastic line suddenly, discontinuously jumps to a higher compression. These theoretical results are the foundations explaining a class of elastic instabilities within curved surfaces that also has biological relevance: for example, in a collaboration with researchers at Princeton and the Flatiron Institute, Shiheng Zhao and Pierre Haas recently showed that a similar mechanical bifurcation within a curved surface underpins the morphogenesis of the hindgut of the fruitfly Drosophila.

Shiheng Zhao and Pierre A. Haas, Phys. Rev. Lett. 135, 247201 (2025)

Understanding complex many-body dynamics in laser-driven molecules is essential for efforts to control chemical reactions using intense light fields.
Ultrashort, high-intensity X-ray pulses from accelerator-based free-electron lasers (FELs) now make it possible to observe—in real time—how strong laser fields reshape molecular structure. Physicists from two Max Planck Institutes, the MPI for Nuclear Physics in Heidelberg and the MPI for the Physics of Complex Systems in Dresden, together with collaborators from the Max Born Institute in Berlin and institutions in Switzerland, the USA, and Japan, have investigated the prototype molecule C₆₀, the iconic football-shaped "Buckminsterfullerene". In this study, an intense femtosecond laser pulse initiates the molecular dynamics, and a subsequent femtosecond X-ray pulse images the evolving structure at a precisely controlled time delay (as illustrated in the figure).
The experiments were conducted at the Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory, an X-ray FEL operated by Stanford University. Only the enormous intensities provided by such facilities make these imaging experiments possible. Since multi-electron dynamics under intense laser irradiation remain extremely challenging to describe theoretically, with a full quantum-mechanical treatment still out of reach, such X-ray "movies" of structural dynamics offer an ideal testbed for advancing our understanding of fundamental quantum processes in increasingly large and complex molecular systems.

Kirsten Schnorr, Sven Augustin, Ulf Saalmann et al., Sci. Adv. 11, eadz1900 (2025)

Roderich Moessner is to be awarded the 2026 Max Born Prize for his outstanding scientific contributions to physics. Prof. Moessner is a director at the Max Planck Institute for the Physics of Complex Systems in Dresden and is also one of the Principal Investigators of the Cluster of Excellence ct.qmat (Complexity and Topology in Quantum Matter).

Prof. Moessner's groundbreaking work on spin liquids, charge stripes in quantum Hall systems, and frustrated magnetism has provided fundamental insights into novel physical phenomena that have helped shape the field of topological solid-state physics worldwide. Roderich Moessner’s research continues to uncover new realms of physical behavior: More recently, he predicted discrete time crystals and verified them experimentally using Google’s Sycamore quantum computer.
Roderich Moessner studied at the University of Oxford, where he completed his doctorate in theoretical physics under John T. Chalker in 1997. After holding a Junior Research Fellowship at New College, Oxford, he moved to Princeton University. From 2001 to 2006, he conducted research at the French National Centre for Scientific Research (CNRS) before returning to Oxford. In 2007, he was appointed as a director of the Max Planck Institute for the Physics of Complex Systems in Dresden. He has also served as an honorary professor at Technische Universität Dresden since 2008. He is also one of the Principal Investigators of the Würzburg–Dresden Cluster of Excellence ct.qmat.

The Max Born Prize is jointly awarded by the British Institute of Physics and the German Physical Society. Established in 1973 in memory of Nobel laureate Max Born, the Max Born Prize honours outstanding and cutting-edge scientific contributions to physics. The award alternates annually between German and British researchers. Born, a German mathematician and physicist persecuted by the Nazi regime, took British citizenship in exile and received the Nobel Prize in Physics in 1954 for his contributions to quantum mechanics. The award will be presented to Prof. Moessner in 2026 in the UK.

Text adapted from a press release of ct.qmat.

“The future belongs to those who collaborate.”
This statement applies not only to science, but also to many other areas of life. The willingness to work together—whether on a small scale or in a broader context—must, however, be continuously encouraged and nurtured.
To involve renowned scientists from outside in this collaboration and to strengthen Dresden’s scientific appeal, the “Physics Prize Dresden” was established. It promotes cooperation between the Max Planck Institute for the Physics of Complex Systems (MPI-PKS) and the Department of Physics at TU Dresden, and is aimed at outstanding researchers whose work is of particular interest to scientists in Dresden.

On November 18, 2025, the Physics Prize Dresden 2025 was awarded to Prof. Igor Herbut of Simon Fraser University in Canada. For a theoretical physicist, it is especially gratifying to discover universal features in seemingly different contexts—and Igor Herbut is ideally qualified for this. Prof. Herbut is a world-leading theoretical physicist with strong mathematical inclinations and broad interests in condensed matter, statistical physics, and field theory.
A look at his extensive publication list quickly reveals several characteristics: First, Prof. Herbut tackles challenging problems. His work combines advanced mathematical methods with deep physical insight. Second, he often collaborates with young scientists. Supporting the next generation is a matter of great importance to him. Prof. Herbut has maintained close ties with the Max Planck Institute for the Physics of Complex Systems for many years. He also visits Dresden regularly and is in close contact with several groups at TU Dresden. Igor Herbut thus embodies in an ideal way the purpose of the Physics Prize Dresden as understood and enabled by its founder, Prof. Peter Fulde—namely, to highlight and promote outstanding research of interest to MPI-PKS and TU Dresden, and to strengthen their connections.

Quantum technologies, such as quantum computers and sensors, rely on the ability to steer the behaviour of quantum particles precisely. However, the process of finding the best way to control a quantum system can be like navigating a vast and rugged surface, called the control landscape. Moreover, control landscapes are not static, and can undergo sudden and dramatic changes as experimental parameters are varied, similar to how water abruptly freezes into ice. These changes, known as control landscape phase transitions, mark critical points where new optimal control strategies suddenly emerge. In a pair of papers, Nicolò Beato, Pranay Patil, and Marín Bukov of the Max Planck Institute for the Physics of Complex Systems have now proposed analytical and numerical techniques to describe these transitions, borrowing tools from statistical physics usually applied to complex systems such as magnets and glasses.
Their work sheds new light on these transitions, which are linked to physical properties of the quantum system, such as the minimum time needed to drive a system from one state to another. By applying their methods to prototypical quantum systems, the researchers characterised their fundamental properties and were able to understand why these transitions arise. Their theory suggests a deep interconnection with the physics of disordered media, such as spin and structural glasses. This research opens up a path toward systematically understanding—and ultimately harnessing—the complexity of quantum control, which is essential for building reliable quantum technologies.

Niccolò Beato, Pranay Patil, and Marín Bukov, Phys. Rev. Lett. 135, 110803 (2025)
Niccolò Beato, Pranay Patil, and Marín Bukov, Phys. Rev. X 15, 041014 (2025)

The application deadline for this call is the 21 of November 2025. Distinguished PKS postdoctoral fellows appear personally along with the departments and groups on the main research page of the institute and are expected to have at least one year of postdoctoral experience at an institution other than the one at which their PhD was awarded. Applications for this fellowship directly after completion of the PhD might be considered in exceptional cases. Please click on the button to see the full advertisement!

Fridtjof Brauns joins the Max Planck Institute for the Physics of Complex Systems (MPIPKS) and the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) as a new research group leader. With his group, “Living and Morphing Matter Theory,” he is interested in self-organization in living systems, how biology controls and harnesses physical instabilities, and how geometry emerges from genes during development. Addressing these questions, Fridtjof uses concepts and ideas from theoretical physics, dynamical systems, and geometry, working in close collaboration with experimentalists.
“Dresden has a very tight connection of experiments and theory, which made it a really attractive place for me,” says Fridtjof. “The Max Planck Society is a wonderful place to focus on science, and I think it's a real privilege to have that freedom. There are many research groups here that I would love to collaborate with in the future, and I'm really looking forward to exploring new research directions here.”
Fridtjof Brauns studied physics and theoretical and mathematical physics at the Ludwig Maximilian University (LMU) in Munich. He also pursued his PhD at the LMU and went from there to the Kavli Institute for Theoretical Physics at the University of California-Santa Barbara for a postdoc with Boris Shraiman and Cristina Marchetti, where he focused on questions in development, cell- and tissue mechanics as well as active matter.
Text: Katrin Boes/MPI-CBG

Tissues deform in the complex shapes of organs and organisms during development. This morphogenesis is often active, resulting from biological processes generating forces within the tissue, but it can also be passive, with deformations resulting from forces imposed at their boundaries by neighbouring tissues.
Shiheng Zhao and Pierre Haas of the Max Planck Institute for the Physics of Complex Systems and the Max Planck Institute of Molecular Cell Biology and Genetics and their experimental collaborators at Princeton University and the Flatiron Institute have now identified the hindgut primordium in the embryos of the fruit fly Drosophila as a model for this boundary-driven morphogenesis. The researchers developed a minimal mechanical model of the hindgut as an elastic ring deforming due to invagination and convergent extension of tissues surrounding the hindgut. This model explains the symmetry-breaking of the shape of the hindgut, with the curvature of the embryo robustly selecting the observed orientation of this shape. They tested their model using different genetic perturbations. On the physical side, this work highlights how curvature controls mechanical bifurcations. More biologically, the research introduces hindgut primordium as a paradigm for understanding inter-tissue coupling and global morphologies in development.

Daniel S. Alber*, Shiheng Zhao*, Alexandre Jacinto, Eric Wieschaus, Stanislav Y. Shvartsman, and Pierre A. Haas, Proc. Natl. Acad. Sci. USA 122, e2505160122 (2025)

The Ig Nobel Prizes honour scientific discoveries that "make people laugh, and then make people think". This year, the laureates in the Physics category are Giacomo Bartolucci, Daniel M. Busiello, Matteo Ciarchi, Alberto Corticelli, Ivan Di Terlizzi, Fabrizio Olmeda, Davide Revignas, and Vincenzo M. Schimmenti, for "for discoveries about the physics of pasta sauce, especially the phase transition that can lead to clumping, which can be a cause of unpleasantness". The researchers, who are current or former researchers at the Max Planck Institute for the Physics of Complex Systems, established starch concentration as the key factor to ensure the stability of the sauce and offered a scientifically optimised recipe so that pasta enthusiasts can get the dish right every single time. Many congratulations!

The work was published as G. Bartolucci et al., Phys. Fluids 37, 044122 (2025) as part of a special issue on "Kitchen Flows".