Article
Materials Science, Multidisciplinary
Max Hering, Han Yan, Johannes Reuther
Summary: This study investigates fracton behavior in classical kagome spin models with different types of elementary spin degrees of freedom, including three-state Potts, XY, and Heisenberg spins, all of which exhibit characteristic subsystem symmetries and fractonlike excitations. The systems show a crossover into a low-temperature glassy phase, where they become trapped in metastable fracton states, and slow equilibration dynamics at low temperatures due to power-law relaxation behavior of defect states, particularly in the case of Heisenberg spins.
Article
Materials Science, Multidisciplinary
Giovanni Canossa, Lode Pollet, Ke Liu
Summary: This article investigates two specific cases of phase transitions that break subsystem symmetries. The models in question are two classical compass models with line-flip and plane-flip symmetries, which correspond to special limits of a Heisenberg-Kitaev Hamiltonian on a cubic lattice. The study shows that these models undergo a hybrid symmetry breaking, wherein the system exhibits distinct symmetry broken patterns in different submanifolds. For example, the system may appear magnetic within a chain or plane, but nematic-like when observed from a higher dimensionality. By using a set of subdimensional order parameters, the symmetry-broken phases are fully characterized, and numerical analysis confirms that both cases undergo a non-standard first-order phase transition. These findings provide new insights into phase transitions involving subsystem symmetries and generalize the concept of conventional spontaneous symmetry breaking.
Article
Materials Science, Multidisciplinary
Luis Benet, Fausto Borgonovi, Felix M. Izrailev, Lea F. Santos
Summary: We study the quantum-classical correspondence for strongly chaotic systems with interacting spin particles and fixed angular momenta. Through analyzing Lyapunov spectra, we find that the largest Lyapunov exponent agrees with the exponent determining the local instability of each individual spin. In the quantum domain, we analyze the Hamiltonian matrix to determine the conditions for quantum chaos based on the model parameters. By comparing the quantum and classical domains, we establish the relationship between quantum quantities and their classical counterparts, such as the local density of states and the chaotic eigenfunctions.
Article
Physics, Multidisciplinary
V. E. Didenko, N. K. Dosmanbetov
Summary: The Kerr-Schild double copy is shown to be a natural extension for all free symmetric gauge fields propagating on (A)dS in any dimension. Like the case of lower-spin, the higher-spin multicopy is associated with zeroth, single, and double copies. The masslike term of the Fronsdal spins field equations, fixed by gauge symmetry and the mass of the zeroth copy, fit remarkably well into the multicopy pattern organized by higher-spin symmetry. This observation adds to the list of miraculous properties of the Kerr solution on the black hole side.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Dennis Schubert, Jonas Richter, Fengping Jin, Kristel Michielsen, Hans De Raedt, Robin Steinigeweg
Summary: The study compares the spin and energy dynamics in quantum and classical spin models on different geometries, focusing on the autocorrelation functions of local densities at formally infinite temperature. The findings suggest that classical or semiclassical simulations can provide a meaningful strategy to analyze the dynamics of quantum many-body models, even for small spin quantum numbers far from the classical limit.
Article
Materials Science, Multidisciplinary
Ashkan Ashrafi Dehkordi, Reza Jahanbazi Goojani, Yaghoub Tadi Beni
Summary: In this paper, the coupling equations dependent on the size of the functionally graded porous flexoelectric cylindrical nanoshell are derived based on non-classical theory. The effects of microstructure and porosity on the shell model are considered using modified flexoelectric strain gradient theory. The formulation is applied to investigate the problem of free vibrations.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Physics, Multidisciplinary
Franz J. Schreiber, Jens Eisert, Johannes Jakob Meyer
Summary: The advent of noisy intermediate-scale quantum computers has led to the exploration of possible applications, especially in quantum machine learning. This research introduces the concept of a classical surrogate, a classical model obtained from a trained quantum learning model that reproduces its input-output relations. The existence of a classical surrogate enhances the applicability of quantum learning strategies but also challenges the advantages of quantum schemes.
PHYSICAL REVIEW LETTERS
(2023)
Article
Quantum Science & Technology
Davide Vodola, Manuel Rispler, Seyong Kim, Markus Mueller
Summary: By mapping the decoding of quantum error correcting codes to classical disordered statistical mechanics models, researchers can determine critical error thresholds and extend this mapping to include multi-parameter noise models. This approach can be used to assess fundamental thresholds of QEC circuits independently of specific decoding strategies, ultimately guiding the development of near-term QEC hardware.
Article
Multidisciplinary Sciences
Kamil K. Kolincio, Max Hirschberger, Jan Masell, Shang Gao, Akiko Kikkawa, Yasujiro Taguchi, Taka-hisa Arima, Naoto Nagaosa, Yoshinori Tokura
Summary: The long-range order of noncoplanar magnetic textures with scalar spin chirality can produce a geometrical Hall effect; finite SSC can be caused by spin canting due to thermal fluctuations; in highly conducting ferromagnets, thermally generated SSC can lead to a gigantic geometrical Hall conductivity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
David van Driel, Guanzhong Wang, Alberto Bordin, Nick van Loo, Francesco Zatelli, Grzegorz P. Mazur, Di Xu, Sasa Gazibegovic, Ghada Badawy, Erik P. A. M. Bakkers, Leo P. Kouwenhoven, Tom Dvir
Summary: Researchers have discovered that spin-filtered measurements can reveal the ground state of Andreev bound states in semiconducting nanowires coupled to superconductors. They directly measured the spin-polarized excitation spectrum of single-electron excitations using a spin-polarized quantum dot and a non-polarized tunnel junction in a three-terminal circuit.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Sofie Janas, Jakob Lass, Ana-Elena Tutueanu, Morten L. Haubro, Christof Niedermayer, Uwe Stuhr, Guangyong Xu, Dharmalingam Prabhakaran, Pascale P. Deen, Sonja Holm-Dahlin, Kim Lefmann
Summary: Neutron spectroscopy on the classical triangular-lattice frustrated antiferromagnet h-YMnO3 shows diffuse, gapless magnetic excitations both below and above the ordering temperature, with an increasing correlation length as temperature approaches zero, resembling critical scattering. The dynamics in the ordered and correlated disordered phase are modeled as critical spin correlations in a two-dimensional magnetic state. The researchers suggest that their findings may offer a general framework for understanding characteristics often associated with classical spin liquids.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Yong-Long Wang, Hao Zhao, Hua Jiang, Hui Liu, Yan-Feng Chen
Summary: The study of relativistic particles confined to a Mobius strip reveals that geometry can lead to variations in gauge potential and mass, resulting in the generation of a monopole magnetic field and quantum spin Hall effects.
Article
Engineering, Mechanical
Jin-Song Pei, Francois Gay-Balmaz, Darby J. Luscher, James L. Beck, Michael D. Todd, Joseph P. Wright, Yu Qiao, Marco B. Quadrelli, Chuck R. Farrar, Nicholas A. J. Lieven
Summary: A family of mem-models, including mem-dashpots, mem-springs, and mem-inerters, is emerging as a new and powerful way of capturing complex nonlinear behaviors of materials and systems. This study demonstrates the connection between absement and damage variables, and the efficiency of generalized momentum in modeling strain ratcheting. It also shows how two formulations of memcapacitive system models for mem-springs are special cases of the Preisach model.
NONLINEAR DYNAMICS
(2021)
Article
Physics, Multidisciplinary
Li-Ping Yang, Zubin Jacob
Summary: This study derives the quantum state of structured photons from quantum field theory, capturing the quantum uncertainty in angular momentum and non-local photonic spin density correlations. It introduces the concept of quantum structured light and explores quantum noise and photon statistics of three-dimensional photonic angular momentum in twisted light pulses.
COMMUNICATIONS PHYSICS
(2021)
Article
Physics, Multidisciplinary
Heinz-Juergen Schmidt, Johannes Richter
Summary: In this paper, we present a generalization of the Luttinger-Tisza-Lyons-Kaplan theory to non-Bravais lattices, by adding Lagrange parameters to the diagonal of the Fourier transformed coupling matrix. We illustrate this approach with examples of modified honeycomb and square lattices, showing that it can obtain various types of ground states.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Physics, Multidisciplinary
Natascha Hedrich, Kai Wagner, Oleksandr V. Pylypovskyi, Brendan J. Shields, Tobias Kosub, Denis D. Sheka, Denys Makarov, Patrick Maletinsky
Summary: The study demonstrated manipulation and interaction of antiferromagnetic domain walls using isolated 180 degree domain walls in a single crystal of Cr2O3, proposing a memory architecture based on topographically defined antiferromagnetic domain walls. These results advance the understanding of domain wall mechanics in antiferromagnets.
Correction
Physics, Multidisciplinary
Natascha Hedrich, Kai Wagner, Oleksandr V. Pylypovskyi, Brendan J. Shields, Tobias Kosub, Denis D. Sheka, Denys Makarov, Patrick Maletinsky
Summary: A correction notice has been published for this paper.
Article
Physics, Applied
Oleksii M. Volkov, Florian Kronast, Claas Abert, Eduardo Sergio Oliveros Mata, Tobias Kosub, Pavlo Makushko, Denise Erb, Oleksandr V. Pylypovskyi, Mohamad-Assaad Mawass, Denis Sheka, Shengqiang Zhou, Jurgen Fassbender, Denys Makarov
Summary: We propose a method to access both the DMI constant and DW damping from static experiments by monitoring the tilt of magnetic DWs in nanostripes. Experimental results show that in perpendicularly magnetized //CrOx/Co/Pt stacks, DWs can be trapped on edge roughness in a metastable tilted state as a result of the DW dynamics driven by an external magnetic field. The measured tilt can be correlated to the DMI strength and DW damping in a self-consistent way based on a theoretical formalism using the collective coordinate approach.
PHYSICAL REVIEW APPLIED
(2021)
Article
Physics, Applied
Oleksandr Pylypovskyi, Yelyzaveta A. Borysenko, Juergen Fassbender, Denis D. Sheka, Denys Makarov
Summary: Chiral antiferromagnets can be tailored using geometrical curvature to produce various effects, such as tilting the direction of vector order parameters and generating a homogeneous Dzyaloshinskii-Moriya interaction. These effects provide an extra degree of freedom in designing spintronic and magnonic devices.
APPLIED PHYSICS LETTERS
(2021)
Article
Multidisciplinary Sciences
Bhartendu Satywali, Volodymyr P. Kravchuk, Liqing Pan, M. Raju, Shikun He, Fusheng Ma, A. P. Petrovic, Markus Garst, Christos Panagopoulos
Summary: Non-collinear magnets exhibit a rich array of dynamic properties at microwave frequencies, hosting nanometre-scale topological textures known as skyrmions. The magnetic resonance study of an [Ir/Fe/Co/Pt] multilayer hosting Neel skyrmions at room temperature reveals distinct resonances with frequencies between 6-12 GHz, showing sensitivity to out-of-plane dipolar coupling. The gyration of stable isolated skyrmions reported in this study encourages the development of new material platforms and applications based on skyrmion resonances, with potential for tuning resonance spectra and expanding functionality over a broadband frequency range.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Applied
Denis D. Sheka
Summary: Curvilinear magnetism, which explores geometry-governed magnetic interactions in curved magnetic wires and films, has seen significant advancements in experimental techniques. This has led to the potential utilization of 3D curved nanomagnets in emerging devices with various applications. The focus is on novel physical effects resulting from the customization of curvature and topology in conventional magnetic materials.
APPLIED PHYSICS LETTERS
(2021)
Review
Chemistry, Multidisciplinary
Denis D. Sheka, Oleksandr Pylypovskyi, Oleksii M. Volkov, Kostiantyn Yershov, Volodymyr P. Kravchuk, Denys Makarov
Summary: Low-dimensional magnetic architectures, such as wires and thin films, play a crucial role in the development of ultrafast and energy-efficient memory, logic, and sensor devices. Curvilinear magnetism, which relies on the geometrical curvature of magnetic architectures, offers a novel approach for tailoring anisotropic and chiral responses. This article summarizes theoretical activities on curvilinear magnetic wires and nanoribbons, explores the emergent interactions and physical effects caused by curvature, and discusses prospective research directions in spintronics, spin-orbitronics, and mechanically flexible architectures for soft robotics.
Article
Physics, Multidisciplinary
Maria Azhar, Volodymyr P. Kravchuk, Markus Garst
Summary: This paper investigates the micromagnetic structure of screw dislocation lines in cubic chiral magnets and finds that different strength dislocations can have a variety of core structures. In particular, the magnetization at the core can be either smooth or singular. Screw dislocations carry a noninteger but finite skyrmion charge and can be manipulated by spin currents, contributing to the topological Hall effect.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Oleksandr Zaiets, Volodymyr P. Kravchuk, Oleksandr Pylypovskyi, Denys Makarov, Denis D. Sheka
Summary: Vertically stacked exchange coupled magnetic heterostructures with cylindrical geometry can exhibit complex noncolinear magnetization patterns. By controlling the interlayer exchange coupling and sample geometrical parameters, the number of circular stripes and the switching between different states can be achieved. This research is of great importance for the engineering of magnetic textures in spintronic devices.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Physics, Applied
Oleksandr Pylypovskyi, Natascha Hedrich, Artem Tomilo, Tobias Kosub, Kai Wagner, Rene Huebner, Brendan Shields, Denis D. Sheka, Juergen Fassbender, Patrick Maletinsky, Denys Makarov
Summary: The search for high-speed and low-energy memory devices is focused on antiferromagnetic thin films in spintronic research. A material model of a granular antiferromagnetic thin film with uniaxial anisotropy is developed, providing fundamental insight into the interaction of antiferromagnetic domain walls with grain boundaries. The model is validated on thin films of the antiferromagnetic insulator Cr2O3, showing complex mazelike domain patterns hosting localized nanoscale domains down to 50 nm. Analysis of high-resolution images of antiferromagnetic domain patterns reveals that the intergrain magnetic parameters can be estimated, providing design rules for granular antiferromagnetic recording media.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Yelyzaveta A. Borysenko, Denis D. Sheka, Juergen Fassbender, Jeroen van den Brink, Denys Makarov, Oleksandr V. Pylypovskyi
Summary: This paper investigates the effects of curvature in ring-shaped antiferromagnetic achiral anisotropic spin chains in strong magnetic fields. The curvature-induced Dzyaloshinskii-Moriya interaction results in a spin-flop transition of first or second order, depending on the ring curvature. In addition, the spatial inhomogeneity of the Neel vector in the spin-flop phase generates a weak ferromagnetic response.
Article
Materials Science, Multidisciplinary
Kostiantyn Yershov, Attila Kakay, Volodymyr P. Kravchuk
Summary: The influence of the geometrical curvature of chiral magnetic films on the static and dynamic properties of hosted skyrmions is theoretically studied. The effects of curvature-induced drift of skyrmions are predicted without any external stimuli. The strength of the driving force depends on the skyrmion type and the motion trajectory is determined by the type of magnetic ordering.
Article
Chemistry, Physical
Gaetano Napoli, Oleksandr Pylypovskyi, Denis D. Sheka, Luigi Vergori
Summary: In this study, a parallel is drawn between ferromagnetic materials and nematic liquid crystals confined on curved surfaces within the framework of continuum theory. It is shown that the combination of extrinsic curvature of the shell and the out-of-plane component of the director field leads to chirality effects. Furthermore, the different nature of the order parameter results in different textures on surfaces with the same topology.
Article
Materials Science, Multidisciplinary
Benjamin Wolba, Olena Gomonay, Volodymyr P. Kravchuk
Summary: Theoretical description of a terahertz nano-oscillator based on an anisotropic antiferromagnetic dynamical element driven by spin torque reveals chaotic behavior with particularly low threshold current near the spin-flop transition. Prior to the appearance of chaos, a regime of quasiperiodic dynamics on the surface of a two-frequency torus may occur.
Article
Materials Science, Multidisciplinary
Oleksandr Pylypovskyi, Artem Tomilo, Denis D. Sheka, Jurgen Fassbender, Denys Makarov
Summary: Understanding the interaction of antiferromagnetic solitons with chiral antiferromagnetic slab boundaries is key for designing future antiferromagnetic spintronic devices. This study establishes a model for the transition from spin lattice to micromagnetic nonlinear sigma model with boundary conditions, and evaluates the impact of boundary and antisymmetric exchange on the vector order parameter. Results show that both types of antiferromagnetic solitons become broader and transform into a mixed structure near the boundary due to the presence of antisymmetric exchange.
