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I will discuss how the bottom-up growth of van der Waals magnets by molecular beam epitaxy (MBE) promotes favourable conditions to stabilize specific magnetic behaviour which has remained elusive on studies with exfoliated bulk crystal flakes – such as 2D-XY anisotropy and enhancement of magnetic exchange driven by self-intercalation. First, I will focus on the successful van-der-Waals epitaxy of a CrCl3 monolayer grown on Graphene/6H-SiC(0001), revealing intrinsic ferromagnetic order with easy-plane anisotropy and a 2D-XY magnetic universality class [1].  This constitutes the first realization of a Berezinskii-Kosterlitz-Thouless (BKT) transition in a 2D magnet, with important implications in the stabilization of topological spin textures with in-plane winding, i.e. merons. The important role of the van der Waals substrate interaction and the underlying crystal symmetry to achieve this rather unsual magnetic behaviour will be discussed, thereby highlighting routes on how to control the anisotropy of 2D magnets via growth and substrate engineering.

Further peculiarities of MBE-grown van der Waals magnets, such as an increase of the Curie Temperature driven by self-intercalation [2], will be shown in the prototypical layered magnet Fe5GeTe2. The epitaxial films exhibit ferromagnetic ordering up to 375 K, concomitant with a sizable Fe occupation within the van der Waals gaps. Supported by first-principles calculations, we infer that the higher magnetic ordering temperature results from an increased exchange interaction among the Fe5GeTe2 layers mediated by Fe within the vdW gaps. Our findings establish self-intercalation during epitaxial growth as an efficient mechanism to achieve high-temperature magnetism in a broad class of van der Waals materials.

[1]  Bedoya-Pinto, et.al. Intrinsic 2D-XY ferromagnetism in a van der Waals monolayer. Science 374 (6567), 616-620 (2021)
[2]  Silinskas, et. al. Self-intercalation as origin of high-temperature ferromagnetism in epitaxially grown Fe5GeTe2 thin films. Physical Review Letters 133, 256702 (2024)

Dr Amilcar Bedoya-Pinto

University of Valencia, Spain

Dr Amilcar Bedoya-Pinto

University of Valencia, Spain

Dr Bedoya-Pinto is a Distinguished Researcher at the Institute of Molecular Science, University of Valencia and leads the group “Epitaxial Quantum Materials and Heterostructures”. He studied Physics at the Technical University of Munich and got a PhD in Condensed Matter Physics at the University of Göttingen, where he was awarded the Dr Berliner-Ungewitter Prize for outstanding PhD theses. He followed up with Post-Doctoral stays at CiC nanoGUNE and Max-Planck Institute of Microstructure Physics. His expertise encompasses semiconductor physics, magnetism and spintronics, as well as epitaxial growth and surface physics. He made important contributions in the field of molecular spintronics, topological semimetals and most recently, in bottom-up grown van der Waals magnets, carrying out the first demonstration of a monolayer 2D ferromagnet with XY anisotropy. Currently, his group aims to study emergent phenomena – due to symmetry breaking- at tailored van der Waals and covalent heterostructures grown by molecular beam epitaxy.

The transition-metal chalcogenides include some of the most important and ubiquitous families of 2D materials. Their van der Waals nature allows for the ready isolation of single layers, while they host an exceptional variety of electronic and magnetic states which can in principle be readily tuned by combining different 2D layers in van der Waals heterostructures [1]. Growth via molecular-beam epitaxy (MBE) should be a premier route to achieve this, but efforts have been hampered by non-uniform layer coverage [2], unfavourable growth morphologies, the presence of significant rotational disorder, and limited growth windows and growth rates. I will discuss how a dramatic enhancement in quality of MBE-grown 2D materials can be achieved by simple substrate pre-treatments which dramatically enhance the epilayer nucleation, in turn facilitating a desired layer-by-layer growth mode [3,4]. I will show how this leads to an expanded growth window for metastable materials, allowing, for example the selective stabilisation of high-coverage CrTe2 and Cr2+εTe3 epitaxial monolayers [5]. This, in turn, opens the door to spectroscopic investigations of their magnetic and electronic structures [5,6], and enables their use to induce magnetism in neighbouring 2D layers via proximity coupling in van der Waals heterostructures [7].

[1] Chhowalla et al., Nat. Chem. 5 (2013)
[2] Rajan et al., Phys. Rev. Mater. 4 (2020) 014003
[3] Rajan et al., Adv. Mater. 36 (2024) 2402254
[4] Rajan et al., APL Mater. 13 (2025) 081123
[5] Kushwaha et al., npj Quantum Materials 10 (2025) 50
[6] Armitage et al., Phys. Rev. B in press (arXiv:2505.07942 (2025))
[7] Kushwaha, Rajan et al., in preparation

Professor Phil King

University of St Andrews, UK

Professor Phil King

University of St Andrews, UK

Phil King is Professor of Physics at the University of St Andrews, UK. He obtained his PhD in surface physics from the University of Warwick in 2009, following which he undertook postdoctoral research at St Andrews and then Cornell University. He returned to St Andrews in 2013, where he leads a group focused on investigating the electronic structure of quantum and 2D materials, and in tuning this via thin-film materials synthesis. He previously held a Royal Society University Research Fellowship, a Leverhulme Trust Research Leadership Award, and an ERC Starting Grant. He was formerly the Director of the EPSRC Centre for Doctoral Training in Condensed Matter Physics, co-founded and -directs the St Andrews Centre for Designer Quantum Materials, and, since 2025, serves as Director of Research in the School of Physics and Astronomy at St Andrews.

The topology of magnetic excitations is an exciting new field of study that merges two mature subjects in condensed matter physics that offers a new way of understanding quantum magnets. Long lifetime, surface localisation, and backscattering protection are some of the characteristics of topologically non-trivial magnetic excitations. Such properties make them attractive for potential applications in spintronic and quantum sensing devices. Experimentally identifying and verifying topological magnetic excitations has been challenging because there is not a single experimental method that can do so.

In this talk I will briefly introduce the theory of topological magnons and present two examples, one a quasi-2D magnet [1,2] and the other a non-coplanar antiferromagnet [3], of how use magneto-Raman spectroscopy in combination with inelastic neutron scattering results to identify these quasiparticles. Our conclusions are enabled by the combination of topological theory, inelastic neutron scattering, and the experimental suite at NIST of unique magneto-Raman spectroscopic instrumentation that enables diffraction-limited, spatially- and polarization-resolved Raman measurements while simultaneously varying the temperature (1.6 K to 400 K), laser wavelength (tunability from visible to near-infrared), and magnetic field (up to 9 T). Time-permitting, I will summarise results on additional 2D van der Waals antiferromagnets [4,5,6] also studied at NIST.

[1] Yufei Li, Thuc T Mai, et al. Phys. Rev. B. 109, 184436 (2024)
[2] Thuc T Mai, Yufei Li, et al. Phys. Rev. B. 111, 104419 (2025)
[3] Ahmed E Fahmy, et al. ArXiv:2512.18534. In review
[4] Thuc T Mai, et al. Sci. Adv. 7, eabj3106 (2021)
[5] Amber McCreary, et al. Nat. Comm. 11, 3879 (2020)
[6] Amber McCreary, et al. Phys. Rev. B. 101, 064416 (2020)

Dr Rolando Valdés Aguilar

National Institute of Standards and Technology, US

Dr Rolando Valdés Aguilar

National Institute of Standards and Technology, US

Dr Rolando Valdés Aguilar obtained his PhD from the University of Maryland, and did two postdoctoral fellowships at the Johns Hopkins University and Los Alamos National Laboratory. Dr Valdés Aguilar then went to the Ohio State University as an assistant professor and now serves as Guest Researcher at the National Institute of Standards and Technology (NIST). His research expertise is on the application of optical spectroscopy techniques to study quantum materials such as topological materials, superconductors, multiferroics, and quantum magnets. Most recently he is using Raman spectroscopy to study quantum magnets with topological magnons as their excitations.

Recently discovered two-dimensional (2D) van der Waals (vdW) magnets offer new opportunities for controlling magnetism via mechanisms such as strain, voltage, and twistronics. Ultrafast laser pulses provide the fastest means of manipulating magnetic properties, yet their effects on spins in 2D magnets remain largely unexplored. In this talk, I will discuss all-optical control of the 2D vdW ferromagnets CrI3 [1] and Cr2Ge2Te6 [2,3].

Our research shows that integrating a thin CrI3 flake with a monolayer of transition metal dichalcogenide WSe2 enables helicity-dependent all-optical switching (AOS) down to a single laser pulse [1]. I will also demonstrate that optical pumping can lead to formation of various spin textures, including reversible transformations between stripe and bubble/skyrmion phases in Cr2Ge2Te6 [2]. Finally, I will discuss thickness dependent remagnetisation dynamics in Cr2Ge2Te6 observed via time-resolved beam-scanning Kerr microscopy [3]. Our findings reveal that reducing the thickness of the 2D magnet enhances heat dissipation to the substrate, significantly shortening the magnetisation recovery time from several nanoseconds to a few hundred picoseconds.

[1] M Dąbrowski, et al. Nat. Commun. 13, 5976, (2022)
[2] M Khela, M Dąbrowski, et al. Nat. Commun. 14, 1378 (2023)
[3] M Dąbrowski, et al. Nat. Commun. 16, 2797, (2025)

Dr Maciej Dabrowski

University of Exeter, UK

Dr Maciej Dabrowski

University of Exeter, UK

Understanding how quantum materials form at the atomic scale is essential for unlocking their extraordinary properties. Single-crystalline phases, especially rare-earth intermetallics, kagome lattices, and germanides, offer a rich platform for exploring strongly correlated electron systems, topological metals, and emergent magnetic phenomena. Achieving these crystals often relies on flux growth, a powerful technique that enables slow, controlled crystallization from a molten medium. Yet, the mechanisms governing nucleation, phase competition, and structural evolution during flux growth remain largely hidden.

Our research employs in situ diffraction as a real-time probe to capture these dynamics, revealing how subtle van der Waals interactions and heterostructure subunits, distinct structural blocks that stack and interlink, guide the assembly of layered architectures. By visualizing growth pathways as they unfold, we identify critical conditions for stabilizing kagome frameworks and complex motifs that host exotic states such as Dirac fermions and unconventional magnetism. Combining predictive design with flux growth and real-time structural insight transforms synthesis into a science of controlled complexity. In this presentation, I will demonstrate how in situ diffraction enables rational strategies for growing rare-earth intermetallic kagome and germanide systems with unprecedented precision, paving the way for quantum functionalities once considered out of reach.

Professor Julia Chan

Baylor University, US

Professor Julia Chan

Baylor University, US

Professor Julia Chan (Ph.D., University of California, Davis) is the Fenn Family Chair in Materials Science at Baylor University. After a National Research Council Postdoctoral Fellow at the National Institute of Standards and Technology, she held faculty positions at Louisiana State University and the University of Texas at Dallas. She returned to Baylor in 2022, where her group focuses on the crystal growth and characterization of novel quantum materials. Professor Chan has published more than 240 peer‑reviewed papers, delivered over 150 invited talks, graduated 25 Ph.D. students, and mentored more than 50 undergraduate researchers. Her honors include the NSF CAREER Award, Sloan Research Fellowship, American Crystallographic Association Margaret C. Etter Award, Iota Sigma Pi Agnes Fay Morgan Award, ACS ExxonMobil Faculty Fellowship, the Baylor Outstanding Alumni Award, the ACS DFW Wilfred T. Doherty Award, and the ACS Southwest Regional Research Award. She has served on editorial boards for Chemistry of Materials and Inorganic Chemistry, and is currently a Deputy Editor of Science Advances. Professor Chan is a Fellow of the AAAS and of the American Chemical Society.

Antiferromagnets offer ultrafast spin dynamics, robustness against stray fields, and rich opportunities for spintronic functionality, yet probing their internal magnetic excitations remains challenging due to their vanishing net magnetization. In this work, we demonstrate a direct mechanical route to excite and detect spin dynamics in a crystalline van der Waals antiferromagnet, chromium trichloride (CrCl₃), by employing surface acoustic waves (SAWs). Using piezoelectric LiNbO₃ substrates with interdigital transducers, we observe clear signatures of acoustic and optical spin-wave resonances driven by SAW irradiation in the gigahertz range. The coupling strength and resonance conditions exhibit pronounced dependencies on temperature and magnetic-field orientation, revealing a sensitivity to minute uniaxial anisotropy fields on the order of millitesla. A theoretical model extending conventional ferromagnetic SAW–magnon coupling formalism to antiferromagnetic systems quantitatively reproduces the experimental behaviour. These findings establish surface acoustic waves as a highly sensitive, non-invasive probe of magnetoelastic interactions in low-dimensional magnets. The demonstrated acoustic antiferromagnetic resonance provides a key platform for exploring dynamic spin–lattice coupling, strain-tunable magnetism, and coherent magnon–phonon control in van der Waals heterostructures.

Professor Yoshichika Otani

University of Tokyo, Japan

Professor Yoshichika Otani

University of Tokyo, Japan

YoshiChika Otani received his PhD from Keio University in 1989. After research positions at Trinity College Dublin and CNRS Grenoble, he joined Keio University as Assistant Professor (1992–1995) and Tohoku University as Associate Professor (1995–2002). He led the Quantum Nano-Scale Magnetics Team at RIKEN FRS (2001–2004) and has been a Professor at the Institute for Solid State Physics, University of Tokyo, since 2004. From 2004 to 2024, he also directed the Quantum Nano-Scale Magnetism Team at RIKEN CEMS. He served as Chair Professor of the LANEF Q-SPIN project until 2024 and is currently a Principal Investigator for the JST ASPIRE Q-Spintronics project. Professor Otani has published over 400 papers (h-index 80) and delivered more than 100 invited and plenary talks worldwide. He coordinated the Nano Spin Conversion Science project (2014–2019), received the 2020 MEXT Commendation for Science and Technology, and served on IUPAP’s Commission on Magnetism (C9) from 2011 to 2022.

Superconductors are materials that conduct electrical current without resistance below a critical temperature due to a mechanism that pairs electrons into coherent quantum states. Their unique properties enable transformative technologies ranging from particle accelerator magnets and MRI scanners to emerging quantum technologies such as qubits and ultrasensitive detectors. At present, all large-scale and commercial applications rely on conventional superconductors, in which the pairing mechanism is well understood and described within the Bardeen–Cooper–Schrieffer (BCS) framework. However, these materials operate only at extremely low temperatures, typically between 1 and 10 K, requiring bulky and energetically expensive cryogenic infrastructures. This not only limits widespread deployment but also raises significant sustainability concerns and hinders miniaturization and portability. High-temperature superconductors offer a possible solution. However, the microscopic mechanism driving high-temperature superconductivity goes beyond BCS theory and remains unknown. Without a predictive understanding of the pairing mechanism, it is impossible to rationally design new superconducting materials with elevated critical temperatures beyond known families.

With my group, we target this long-term ambitious project. We developed a theoretical framework and code implementation for the simultaneous solution of the superconducting (Bogoliubov-de Gennes, BdG) and electronic (Density Functional Theory, DFT) problems. Our method, SIESTA-BdG, is implemented in SIESTA, a first-principles DFT code for material simulations. Our unified approach describes both conventional and unconventional superconducting phases, and enables a description of inhomogeneous superconductors, heterostructures, and proximity induced superconductivity. We demonstrate the validity, accuracy, and efficiency of SIESTA-BdG by computing physically relevant quantities (superconducting charge density, band structure, superconducting gap features, density of states) for conventional singlet (Nb, Pb) and unconventional (FeSe) superconductors. We find excellent agreement with experiments. SIESTA-BdG forms the basis for modeling quantum transport in superconducting devices, and to bridge DFT with Dynamical Mean-Field Theory (DMFT) to model high-temperature superconductivity in strongly correlated electron systems.

Professor Zeila Zanolli

Utrecht University, Netherlands

Professor Zeila Zanolli

Utrecht University, Netherlands

Zeila Zanolli is a a Full Professor in Theory and Simulations of Quantum Materials at Utrecht University, where she is leading the “Quantum Materials by Design” group. She is recognized world-wide for her works in first-principles simulations of Quantum Materials, and for establishing on a quantitative basis the interplay between topology, superconductivity, magnetism, and exciton physics. She has led the implementation of superconducting Density Functional Theory in the Open-Source code SIESTA, making the systematic study of complex forms superconductivity (for instance, proximity induced, spin-triplet, high-temperature superconductivity) in addition to conventional ones. She is Deputy Chair or the European Theoretical Spectroscopy Facility, a knowledge center and research newtwork across Europe and the United in theoretical spectroscopy. She is serving in several international boards on Quantum Materials (European Physical Society, NWO Quantum Committee, Dutch Chemical Society) and atomistic simulations (Psi-k working group “Quantum materials driven by correlations, topology or spin”). 

The non-volatile spin-torque memory is emerging as a key enabler of low-power technologies, which are expected to spread across large markets, from embedded memories to the Internet of Things. We present our perspective on spin-orbit torque (SOT) device applications using the emerging family of quantum van der Waals materials. Previous proposals for field-free SOT switching of perpendicular magnetic anisotropy (PMA) require either additional magnetic layers or structural engineering, which not only complicate the fabrication process but also impede the scalability and stability. Exploiting the out-of-plane damping-like torque could be a solution for this challenge. Here we experimentally demonstrate field-free switching of PMA CoFeB at room temperature utilising out-of-plane (z) spins from Weyl semimetals, TaIrTe4 and PtTe2/WTe2. Both in-plane and out-of-plane spin Hall conductivities are almost one order of magnitude larger than those from other 2D materials and antiferromagnets, leading to substantial switching power reduction. Notably, the highest out-of-plane spin Hall conductivity in PtTe2/WTe2 bilayers is attributed to spin-to-spin conversion in WTe2 induced by crystal asymmetry. Finally, we show a proof of concept RF energy harvesting device using the nonlinear Hall effect (NLHE) induced by crystal symmetry breaking. Our works open a door to realising room-temperature applications based on 2D materials.

Dr Hyunsoo Yang

National University of Singapore, Singapore

Dr Hyunsoo Yang

National University of Singapore, Singapore

Hyunsoo Yang is a Professor in the Department of Electrical and Computer Engineering, National University of Singapore (NUS), working on various magnetic materials and devices for spintronics applications. He worked at C&S technology, LG Electronics in San Jose, and Intelligent Fiber Optic Systems, California. He received his Doctorate from Stanford University. From 2004-2007, he was at IBM Almaden Research Center. He has authored more than 260 journal articles, given 200 invited presentations, and holds 20 patents. He was a recipient of the Outstanding Dissertation Award from the American Physical Society (GMAG), IEEE Magnetics Society Distinguished Lecturer, Minister of Science ICT award, Mid-Career Award of the IEEE Magnetics Society, AAIA Fellow, IEEE Fellow, and APS Fellow.

Moiré magnetism featured by stacking engineered atomic registry and lattice interactions has recently emerged as an appealing quantum state of matter at the forefront of condensed matter physics research. Nanoscale imaging of moiré magnets is highly desirable and serves as a prerequisite to investigate a broad range of intriguing physics underlying the interplay between topology, electronic correlations, and unconventional magnetism. In this talk, I will present our recent work on using nitrogen-vacancy (NV) centres to perform nanoscale quantum sensing and imaging of magnetic domains and spin fluctuations in twisted double trilayer (tDT) chromium triiodide CrI3. We show that intrinsic moiré domains of opposite magnetizations appear over arrays of moiré supercells in low-twist-angle tDT CrI3 [1]. In addition, spin fluctuations measured in tDT CrI3 reveal two distinct magnetic phase transitions with separate critical temperatures within a moiré supercell [2]. Our results enrich the current understanding of exotic magnetic phases sustained by moiré magnetism and highlight the opportunities provided by quantum spin sensors in probing microscopic spin related phenomena on two-dimensional flatland. Lastly, I will extend my discussion to briefly present our ongoing efforts on exploring next-generation van der Waals quantum sensing technologies using color centres beyond NVs [3, 4, 5].

References:
1. M Huang et al., Nat. Commun. 14, 5259 (2023)
2. S Li et al., Nat. Commun. 15, 5712 (2024)
3. M Huang et al., Nat. Commun. 13, 5369 (2022)
4. J Zhou et al., Sci. Adv. 10, eadk8495 (2024)
5. X Zhang et al., arXiv:2502.04561 (2025)

Professor Chunhui (Rita) Du

Georgia Institute of Technology, US

Professor Chunhui (Rita) Du

Georgia Institute of Technology, US

Chunhui Du is an Associate Professor of Physics at Georgia Institute of Technology. She received her PhD in Physics from The Ohio State University in 2015. She worked as a postdoctoral fellow at Harvard University from 2015 to 2019. Chunhui’s current research focuses on developing color center-based quantum sensing tools to study emergent condensed matter physics. Chunhui Du has received the National Science Foundation Career Award (2021), Air Force Office of Scientific Research Young Investigator Award (2021), Department of Energy Early Career Award (2022), Office of Naval Research Young Investigator Award (2023), Sloan Research Fellowship (2024), and International Union of Pure and Applied Physics Early Career Scientist Prize (2022).