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Hybrid Correlated States and Dynamics in Quantum Materials

Correlated states of electrons give rise to quantum matter, such as ordered magnets, spin liquids, superconductors, and topological materials. In lower dimensions, correlations assume a still pronounced importance. The exciting phenomena hosted and technological applications promised by these states of matter have further inspired the scientific community to engineer hybrids where different ingredients for correlations are provided by separate materials coupled together. Thus, such low-dimensional hybrid nanostructures have enabled engineering novel states of matter with intriguing physics, often not admitted by any single platform.

The workshop shall bring together experts and young researchers from three different communities: (i) Magnetism and Spintronics, (ii) Superconductivity and Strongly Correlated Electrons, and (iii) Low-dimensional nanostructures. The purview includes coherent and incoherent magnetization dynamics in conjunction with the various spintronics effects that allow its manipulation and detection. A key topic will be the recently discovered nonreciprocal effects in magnets e.g., chiral magnons, as well as superconductors, e.g., the superconducting diode effect.

Recent discoveries regarding two-dimensional materials, multi-orbital superconductivity, Ising superconductors, topological superconductivity and quantum sensors coupled to magnets will also be central to the workshop portfolio. Employing fluctuations of currents (e.g, flow of spin or vortices) to probe the quantum nature of transport will form an exciting topic of discussion across communities. Finally, the case of spin fluctuations mediated superconductivity, that is believed to underlie a wide range of unconventional superconductors can best be discussed with the three communities present at the workshop.

Nanomagnetism in 3D

The scientific and technological exploration of three-dimensional magnetic nanostructures is an emerging research field with exciting novel physical phenomena, originating from the increased complexity in spin textures, topology, and frustration in three dimensions. Tailored three-dimensional nanomagnetic structures, including in artificial spin ice systems or magnonics will enable novel applications in magnetic sensor and information processing technologies with improved energy efficiency, processing speed, functionalities, and miniaturization of future spintronic devices. Another approach to explore and harness the full three-dimensional space is to use curvature as a design parameter, where the local curvature impacts physical properties across multiple length scales, ranging from the macroscopic to the nanoscale at interfaces and inhomogeneities in materials with structural, chemical, electronic, and magnetic short-range order.

In quantum materials, where correlations, entanglement, and topology dominate, the local curvature opens the path to novel phenomena that have recently emerged and could have a dramatic impact on future fundamental and applied studies of materials. Particularly, magnetic systems hosting non-collinear and topological states and 3D magnetic nanostructures strongly benefit from treating curvature as a new design parameter to explore prospective applications in the magnetic field and stress sensing, micro-robotics, and information processing and storage.
Exploring 3d nanomagnetism requires advances in modelling/theory, synthesis/fabrication, and state-of-the-art nanoscale characterization techniques to understand, realize and control the properties, behavior, and functionalities of these novel magnetic nanostructures.

Terahertz Spintronics: toward Terahertz Spin-based Devices

THz spintronics is a novel research field that combines magnetism and spintronic with ultrafast optics. Although ultrafast demagnetization of ferromagnetic materials at picosecond timescale has been first observed already three decades ago, recent years have seen the rapid development of THz spintronic devices stemming from ground breaking studies. Many studies pushed the GHz limits of standard spintronic devices to the THz range by investigating new materials and spin-orbit interactions at ultrafast time scale. Especially, the development of broadband and high power spintronic THz emitters based on simple nanometer thin ferromagnetic / heavy metal bilayers holds the prospect to extend the THz field and widen its applications that has long while been limited to niches for astronomers and spectroscopists.

In the last years, the numerous improvements made in material research (such as on topological insulators and antiferromagnetic materials), interface quality and device engineering have been central to both explore spin-based physics at THz frequencies and investigate to new concepts of spin based THz devices. These cover the full THz block chain (broad and narrowband THz generation and detection, together with control of radiation properties such as polarization and ellipticity) as well as new approaches for THz imaging and encoding THz information. The widespread interest and progress in spin-based THz physics and devices continues to accelerate requiring joint efforts from magnetism, optics and engineering research communities. This workshop will bring together world-leading scientists from these broad range of communities, generating further collaborations and developmentsin this emerging field.

Young Research Leaders Group Workshop: Recent advances in non-equilibrium and magnetic phenomena

In nature, all the most interesting phenomena are non-equilibrium processes, whether it be star explosions, hurricanes or electrons flowing in metals. In recent decades, the invention of new theoretical tools combined with considerable gains in computational power have enabled physicists to investigate and understand increasingly sophisticated non-equilibrium systems.
Magnetic systems provide an excellent playground for investigating non-equilibrium phenomena. Spins couple effectively to temperature gradients, oscillating magnetic fields, charge and heat currents, or laser pulses. This gives rise to phenomena like magnon BEC, the ultrafast switching of magnetic domains, novel types of phase transitions, or rapidly moving magnetic skyrmions and domain walls.
At the same time, the language of quantum magnetism can also be used to describe completely different kinds of systems, for example ultracold atoms in cavities or the qubits of quantum computers. These systems provide new ideas and challenges to the field of non-equilibrium magnetism, e.g., on the role of dissipation, measurement and entanglement.

By bringing together young researchers from both magnetism and more broad non-equilibrium topics with theoretical and experimental backgrounds we hope to learn about each others’ areas of expertise and build future collaborations to advance these fields. Science benefits from diversity, open communication, and different perspectives, and special care has been taken to make this event inclusive and gender-balanced.

Non-equilibrium Quantum Materials Design

Quantum materials driven out of equilibrium by strong electric fields exhibit phenomena that challenge our physical understanding of solids and could be implemented in future device technologies. Examples include photo- and current-induced transitions to metastable hidden phases, the ultrafast optical manipulation of ferroelectricity and magnetism, light-induced superconductivity, and the creation of photon-dressed topological states. While much progress has been made in characterizing these effects, turning them into real-world functionalities requires stabilizing them at high temperature, on long time scales, and with minimal input power. These challenges are inherently of a materials nature. The focus of this workshop is to bring together experts in quantum materials synthesis (single crystals, thin films, vdW heterostructures) with experimentalists and theorists investigating non-equilibrium phenomena to spark a new generation of non-equilibrium quantum materials design – that is, to create quantum materials that are specifically designed for their out-of-equilibrium response to optical and electrical perturbations. The long-term goal is to create a feedback loop between materials synthesis, experimental characterization and theory for non-equilibrium physics, similar to the successful strategies employed in equilibrium quantum materials design.

Quantum Spinoptics

The conference aims at the interdisciplinary experiment of bringing together experts from solid state and quantum optics, in order to foster dialogue at the interface of the two communities. The goal is to plant the seed of a novel hybrid research area, where solid state systems are treated on the same footing as AMO driven-dissipative platforms, and, viceversa, where quantum optics can be reshaped by using concepts from spintronics, magnetism and the physics of correlated materials.We invite and encourage the contribution of selected speakers advancing the frontiers of any of the following fields:(i) dynamical phase transitions in driven-dissipative atomic or spin ensembles, ranging from traditional AMO platforms to spintronics and solid state devices;
(ii) quantum optics-inspired pumping schemes applied to condensed matter models;
(iii) correlated emission and dissipative engineering to build entangled states, and shape novel sub- and superradiant phenomena;
(iv) noise sensing and engineering in light-matter interfaces and NV/color centers.

Altermagnetism: Emerging Opportunities in a New Magnetic Phase

This workshop focuses on the emerging magnetic material class of altermagnets. This recently discovered magnetic phase is separate from the ferromagnetic and antiferromagnetic phases that we are used to. The new altermagnetic class shows compensated magnetic ordering and alternating spin-polarization in both the direct and momentum space, with a d-wave (or higher even-parity wave) symmetry. Altermagnets span a large range of materials from insulators to superconductors, and exhibit properties characteristic of ferromagnetism, antiferromagnetism, and other unique properties that neither of the two previously known classes have.

The novel properties of altermagnets have links to many fields of research, such as spintronics, ultra-fast photo-magnetism, neuromorphics, multiferroics, magnonics, topological matter, or superconductivity. The workshop brings together junior and senior scientists from diverse research fields to explore this fascinating newly discovered magnetic phase.

The exotic phases arising from the complex interplay between the electron and the elementary excitation such as phonons, magnons, etc. is one of the prominent aspects of condensed matter physics. The complex interplay often results in different competing ground states with different microscopic properties and different low energy excitations. Disrupting the system by external stimuli such as changing temperature, applying pressure, or doping with different chemical elements, one can manipulate through different phases and try to understand the microscopic multiple degrees of freedom in correlated many body systems. In addition, complex systems offer a great deal of real world applications, however, sufficient understanding and knowledge of many body interactions is first necessary on a fundamental level.
In this regard, the Elasto-Q-Mat Summer School “Interplay of multiple degrees of freedom – charge, spin and lattice” is intended to bring the state of the art expertise in the field of condensed matter physics to educate our PhD student within the SFB Transregio 288 project. Thus, our students have the opportunity to become familiar with the current research both in terms of theoretical and experimental perspective in the diverse field of many body systems.

Orbitronics: from Topological Matter to next Level Electronics

This workshop aims to boost the new field of orbitronics – a next generation device technology which utilizes the orbital current as an information carrier. The orbital current is expected to be crucial in understanding physical properties of topological matters and to interact with various orders and quasi-particle excitations in nontrivial ways, which may shed lights on unresolved puzzles in correlated matters and lead to discoveries of exotic quantum phenomena. The workshop highlights the emerging concept of the orbital current from the perspective of topology and strong correlation, which are two major pillars of contemporary condensed matter physics, and seek for a novel route to achieving orbitronic devices with different materials such as van der Waals 2D materials, topological matters, oxides, surfaces and interfaces. This would not only have significant impact on next-generation of spin-torque-based memories and devices but also open a new venue for spintronics and valleytronics. The envisioned impact of the workshop is to review status-of-the-art and to discuss challenges and future directions of orbitronics by gathering both young and renowned researchers from condensed matter physics, material science, and nanotechnology.

Spins, Orbits, Charges, and Heat in Magnets

This SPICE Young Research Leaders Group Workshop serves as a melting pot of researchers to discuss recent developments in our understanding of the interplay between magnetism and spin, charge, orbital, and heat transport. What once began with spin-polarized electric currents in ferromagnets and the giant magnetoresistance, today is an internationally overarching research field known as spintronics. The last two decades, in particular, saw the consolidation of spintronics into modern solid state research. This was possible in large parts thanks to the experimental confirmation of the spin Hall effect and its inverse counterpart that enables electrical detection of pure spin currents. By now, it is known that the electronic spin not only couples to magnetic but also electric fields and heat gradients, adding interconversion phenomena between spin, charge, orbital degrees of freedom and heat to the spintronic inventory, examples being the spin Seebeck, spin Nernst, Edelstein, and orbital Hall effects. Being inspired by both the uncovering of fundamental physics as well as the vision that spin will serve as an information carrier, the spintronics community studied a broad range of material classes, including normal, topological, and magnetic metals as well as topological and magnetic insulators. Magnets, in particular, proved to contain a wealth of surprises, exemplified by topological magnons, topological Hall effects in skyrmion crystals, anomalous Hall effects and spin splitting in antiferromagnets, and the magnetic spin Hall effect. These findings constitute the chalk with which to draw the outlines of next-generation technologies, such as antiferromagnetic and topological spintronics, (topological) magnonics, obitronics, etc.