Article
Chemistry, Multidisciplinary
Yaowei Hu, Matthieu Picher, Marlene Palluel, Nathalie Daro, Eric Freysz, Laurentiu Stoleriu, Cristian Enachescu, Guillaume Chastanet, Florian Banhart
Summary: The unusual expansion dynamics of individual spin crossover nanoparticles were investigated using ultrafast transmission electron microscopy. Upon exposure to nanosecond laser pulses, the particles exhibited significant length oscillations during and after expansion. The observed oscillation period of 50-100 ns was similar to the time required for the particles to transition between low-spin and high-spin states. Monte Carlo calculations incorporating elastic and thermal coupling between molecules within a crystalline spin crossover particle were able to explain the observed length oscillations. The system underwent repeated transitions between the two spin states until relaxation in the high-spin state occurred due to energy dissipation.
Review
Chemistry, Inorganic & Nuclear
Pablo J. Gonzalez, Maria G. Rivas, Felix M. Ferroni, Alberto C. Rizzi, Carlos D. Brondino
Summary: Oxidoreductases containing transition metal ions play crucial roles in living organisms, serving as both active sites for substrate conversion and electron transfer centers. These enzymes bind substrates and external electron donors/acceptors at distant protein sites for electron exchange involved in redox reactions. Intra-protein electron transfer occurs through specific pathways connecting distant metal cofactors, which may also be magnetically coupled.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Chemistry, Physical
Zirui Dong, Yubo Zhang, Jun Luo, Ying Jiang, Zhiyang Yu, Nan Zhao, Liusuo Wu, Yurong Ruan, Fang Zhang, Kai Guo, Jiye Zhang, Wenqing Zhang
Summary: In this study, metallic compounds, TiFexCu2x-1Sb and TiFe1.33Sb, were discovered to exhibit a thermopower exceeding many thermoelectric semiconductors and a dimensionless figure of merit comparable to state-of-the-art thermoelectric materials. The high thermoelectric performance was found to be correlated with the non-Fermi-liquid quantum criticality and magnetic fluctuation.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Physics, Condensed Matter
Xiao-Wei Zhang, Ting Cao
Summary: In this study, we investigate the coupling between excitons and phonons in two-dimensional transition metal dichalcogenides, focusing on the spin-nonconserving relaxation channel. Our calculations reveal that phonons can induce effective in-plane magnetic fields to flip the spin of excitons, providing relaxation channels complementary to the spin-conserving relaxation. Furthermore, we calculate the temperature-dependent spin-flip exciton-phonon relaxation times. This study not only presents a theoretical understanding of spin-flip exciton relaxation dynamics in two-dimensional materials, but also provides a basis for experimental measurements.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Optics
Bei Xu, Zhongze Guo, Qiang Gu
Summary: In this study, collective excitation modes in a general 3D homogeneous spin-3/2 Fermi gas with spin-dependent contact interactions are investigated using two-particle Green's functions and diagram techniques. The energy spectra for charge-density waves and transverse spin-density waves are obtained, showing gapless behavior and linear dependence on the wave vector q. The slopes of the spectra vary with the interaction parameters. The results also reveal that the spin-mixing interaction affects the transverse spin-density waves but not the charge-density modes.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Jeongheon Choe, David Lujan, Martin Rodriguez-Vega, Zhipeng Ye, Aritz Leonardo, Jiamin Quan, T. Nathan Nunley, Liang-Juan Chang, Shang-Fan Lee, Jiaqiang Yan, Gregory A. Fiete, Rui He, Xiaoqin Li
Summary: Through investigating the phonon spectra of MnBi2Te4, we found the effects of couplings between electron, spin, and lattice on the material properties, and observed an increase in electron-phonon coupling with decreasing sample thickness.
Article
Chemistry, Multidisciplinary
Carla Boix-Constant, Samuel Manas-Valero, Alberto M. Ruiz, Andrey Rybakov, Krzysztof Aleksander Konieczny, Sebastien Pillet, Jose J. Baldovi, Eugenio Coronado
Summary: 2D magnetic materials, particularly CrSBr, exhibit interesting magnetic properties and offer potential applications in spintronics and magnonics. The magneto-transport properties of CrSBr vertical heterostructures in the 2D limit are investigated, revealing low-dimensional characteristics and spin-valve behavior. CrSBr monolayer/bilayer serves as an excellent platform for studying and controlling field-induced phenomena in two dimensions.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Zhao-xia Pang, Yong-chun Zhao, Wei-Xiao Ji, Yong Wang, Ping Li
Summary: The research presents a novel nodal-ring semimetal in the form of a 2D Ta2 monolayer, which forms six closed rings in the lattice with resistance to SOC. The nodal-ring bands at the K point in Ta exhibit characteristics of valley splitting and spin polarization due to the breaking of inversion symmetry and SOC. Additionally, interesting negative differential resistance effects were found in the transport properties of this material.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Nanoscience & Nanotechnology
Na Li, Qian Xia, Wei-Xiao Ji, Meng Ding, Ping Li, Shu-Feng Zhang, Sheng-Shi Li
Summary: We predict a new 2D ferromagnetic semiconductor MnCoO6Bi2 with spontaneous valley polarization by first-principles calculations. The material exhibits a large valley polarization strength of 254 meV and a ferromagnetic Curie temperature of 214 K, allowing the observation of anomalous valley Hall effects. The band structure with valley polarization can be maintained under external biaxial strains between -6% and 6%. This discovery provides an ideal platform for exploring valleytronic physics in 2D magnetic materials.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2023)
Article
Physics, Multidisciplinary
Jun Yong Khoo, Falko Pientka, Inti Sodemann
Summary: Metallic Fermi liquids and U(1) spin liquids exhibit the same universal transverse conductivity under specific conditions, behaving as metals in a certain regime despite appearing insulating in standard transport experiments. Fluctuations in transverse current result in a directly probed low-frequency magnetic noise, controlled purely by the geometry of the Fermi surface and independent of kinematic details of quasi-particles.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Jing Xu, Xueli Huang, Xiyue Cheng, Myung-Hwan Whangbo, Shuiquan Deng
Summary: By using high-throughput calculations and energy-screening techniques, researchers have found that the heat-induced blueshift in luminescent materials is caused by the energy dependence on the distance between dopant and metal-cation vacancy, as well as the coupling between ion vibrations and electronic states.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Jennifer E. DeMell, Ivan Naumov, Gregory M. Stephen, Nicholas A. Blumenschein, Y. -J. Leo Sun, Adrian Fedorko, Jeremy T. Robinson, Paul M. Campbell, Patrick J. Taylor, Don Heiman, Pratibha Dev, Aubrey T. Hanbicki, Adam L. Friedman
Summary: Mechanical stacking of two dissimilar materials can lead to unexpected changes in behavior of heterostructures. A study of the heterostructure formed by the topological crystalline insulator Pb0.24Sn0.76Te and graphene reveals the formation of a 2D electron gas due to the contact between a polar and a nonpolar surface. The study also observes spin-momentum locking at lower temperatures that transitions to regular spin channel transport around 40K.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Xiao Chen, Yuxiang Bu
Summary: Small perfluorocycloalkanes and cage-shaped perfluoroalkanes can effectively capture excess electrons and form solvated electron ( esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ ) systems. This study investigates the influence of esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ on the indirect nuclear spin-spin coupling (J-coupling) in perfluoroalkane esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ systems through density functional theory calculations. Unusual trans-(Ne)J(FF)-couplings and (Ne)J(FF)-couplings are observed in e@c-CnF2n (n=3, 4, 5) and e@CnFn (n=4, 6, 8). The coupling mechanism involves both through-esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ (T-SE) and through-bonds (T-B)/through-space (T-S) transmission paths. The study provides insights into the mediating role of esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ in coupling information exchange and proposes a new esol- ${{\rm{e}}_{{\rm{sol}}}<^>- }$ -based coupling mechanism.
Review
Materials Science, Multidisciplinary
Shishir Mundra, Gabriel Samson, Giulia Masi, Rebecca Achenbach, David M. Bastidas, Susan A. Bernal, Maria C. Bignozzi, Maria Criado, Martin Cyr, Nina Gartner, Stefanie von Greve-Dierfeld, Andraz Legat, Ali Nikoonasab, John L. Provis, Michael Raupach, Gregor J. G. Gluth
Summary: This review by EFC WP11-Task Force on the corrosion of steel in alkali-activated materials (AAMs) reveals that AAMs have important differences compared to Portland cement, mainly due to variations in pore solution compositions. High sulfide concentrations in blast furnace slag-based AAMs result in distinctive anodic polarization curves, unusually low open circuit potentials, and low polarization resistances, which can be incorrectly interpreted as active corrosion of steel reinforcement. Further research is needed to investigate the influence of the steel-concrete interface on the susceptibility of steel to corrosion in AAMs. Less commonly used electrochemical methods present opportunities for future progress in this field.
MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
(2023)
Review
Materials Science, Multidisciplinary
Yan Cao, Ye Sheng, Xin Li, Lili Xi, Jiong Yang
Summary: Materials genome methods play a crucial role in accelerating the discovery of high-performance novel materials, especially in the field of thermoelectric materials. These methods, including high-throughput calculation, database construction, and machine learning, enable more efficient screening of new materials and accelerate experimental development.
FRONTIERS IN MATERIALS
(2022)
Article
Chemistry, Physical
Yara Alsaadawi, Anna Eichler-Volf, Michael Heigl, Peter Zahn, Manfred Albrecht, Artur Erbe
Summary: Colloidal Janus microparticles can be propelled by controlled chemical reactions, while clusters of magnetic Janus particles demonstrate propagation motion driven by the catalytic decomposition of H2O2 on their metallic caps. The spatial arrangement of the magnetic Janus particles can be influenced by external magnetic fields, and the motion of particle clusters is determined by the arrangement of the particles and caps.
EUROPEAN PHYSICAL JOURNAL E
(2021)
Article
Multidisciplinary Sciences
Philip Beck, Lucas Schneider, Levente Rozsa, Krisztian Palotas, Andras Laszloffy, Laszlo Szunyogh, Jens Wiebe, Roland Wiesendanger
Summary: The research revealed the splitting of atomic Shiba orbitals in antiferromagnetically coupled Mn dimers on a Nb(110) surface due to spin-orbit coupling and broken inversion symmetry, highlighting the significant influence of these previously unconsidered factors on the formation of Shiba bands in superconducting systems.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Andras Laszloffy, Krisztian Palotas, Levente Rozsa, Laszlo Szunyogh
Summary: The study focuses on the electronic and magnetic structure of Mn and Fe clusters on the Nb(110) surface, revealing that the magnetic ground state of atomic chains is influenced by nearest-neighbor isotropic interactions. A spin-spiral ground state is observed for Fe chains along the [1 (1) over bar0] direction, as a result of the frustration of isotropic interactions, with a flat spin-spiral dispersion relation identified.
Article
Chemistry, Multidisciplinary
Ahmad Echresh, Himani Arora, Florian Fuchs, Zichao Li, Rene Huebner, Slawomir Prucnal, Joerg Schuster, Peter Zahn, Manfred Helm, Shengqiang Zhou, Artur Erbe, Lars Rebohle, Yordan M. Georgiev
Summary: A symmetric Hall bar configuration was used to fabricate highly p-type germanium nanowires and check their homogeneity in terms of resistivity and Hall coefficient. It was found that with decreasing nanowire width, resistivity increases and carrier concentration decreases.
Article
Physics, Condensed Matter
A. Deak, J. Jackson, B. Nyari, L. Szunyogh
Summary: Incommensurate magnetism in CrB2 is investigated using a spin model based on density functional theory calculations. The study reveals significant differences in the Heisenberg exchange interactions derived from the paramagnetic phase when applying the disordered local moment (DLM) theory compared to treating the material as a ferromagnet, with the DLM theory offering a more realistic description. The calculations show strong ferromagnetic interactions between Cr planes but frustrated interactions within the planes. The theory successfully reproduces the q-vector of the incommensurate spin spiral state, while the ground state ordering vector is sensitive to exchange interactions. The observed low Mel temperature is attributed to the strong geometric frustration of the exchange interactions.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Chemistry, Physical
Mani Lokamani, Filip Kilibarda, Florian Guenther, Jeffrey Kelling, Alexander Strobel, Peter Zahn, Guido Juckeland, Kurt V. Gothelf, Elke Scheer, Sibylle Gemming, Artur Erbe
Summary: The current-voltage characteristics of a single-molecule junction depend on the electronic coupling between the electrodes and the molecule's transport channels. This coupling, known as Gamma, is influenced by the choice of anchoring groups and their positions on the tip facets as well as the tip-tip separation. In this study, experiments on a specific molecule, N,N'-bis(5-ethynylbenzenethiol-salicylidene)ethylenediamine, using mechanically controllable break junction, reveal the stretch evolution of Gamma with increasing tip-tip separation. A dynamic simulation approach successfully models this stretch evolution and establishes a connection to the microscopic structure of the single-molecule junction.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Multidisciplinary
Philip Beck, Bendeguz Nyari, Lucas Schneider, Levente Rozsa, Andras Laszloffy, Krisztian Palotas, Laszlo Szunyogh, Balazs Ujfalussy, Jens Wiebe, Roland Wiesendanger
Summary: By introducing an atomic layer of gold on a niobium surface, which combines strong spin-orbit coupling and a large superconducting gap, defect-free iron chains were assembled using a scanning tunneling microscope tip, revealing ungapped Yu-Shiba-Rusinov bands in the ferromagnetic chain. By artificially imposing a spin spiral state, a minigap opening and zero-energy edge state formation were observed, providing a new method for screening materials that can host Majorana edge modes protected by large topological gaps.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Tobias Dannegger, Andras Deak, Levente Rozsa, E. Galindez-Ruales, Shubhankar Das, Eunchong Baek, Mathias Klaeui, Laszlo Szunyogh, Ulrich Nowak
Summary: In this study, ab initio calculations were performed to investigate the tensorial exchange interactions of hematite, and a semiclassical Heisenberg spin model was used to understand its magnetic properties. Atomistic spin dynamics simulations were carried out to calculate the equilibrium properties and phase transitions of hematite, particularly the Morin transition. The computed isotropic and Dzyaloshinskii-Moriya interactions were found to agree well with experimental measurements of the Neel temperature and weak ferromagnetic canting angle. Our simulations revealed the delicate balance between dipole-dipole interactions and on-site anisotropies in determining the magnetic phase of the material. Comparison with spin-Hall magnetoresistance measurements on a hematite single crystal showed deviations of the critical behavior at low temperatures, which were attributed to the quantum nature of the fluctuations driving the phase transitions.
Article
Materials Science, Multidisciplinary
Gabriel Martinez-Carracedo, Laszlo Oroszlany, Amador Garcia-Fuente, Laszlo Szunyogh, Jaime Ferrer
Summary: Recently, the magnetic response of synthesized graphene triangulene chains was analyzed using scanning tunneling microscopy methods. Building on this study, the exchange bilinear and biquadratic constants of the chains were determined through calculations of two-spin rotations. The analysis focused on open-ended, odd-numbered chains that exhibited a triplet ground state formed by paired edge states. Three experimental approaches to trigger and control a singlet-triplet spin transition were proposed, including two methods based on mechanical distortion and one method based on the application of an electric field.
Article
Materials Science, Multidisciplinary
Severin Selzer, Leandro Salemi, Andras Deak, Eszter Simon, Laszlo Szunyogh, Peter M. Oppeneer, Ulrich Nowak
Summary: This study investigates the current-induced switching in Mn2Au through first principles calculations and atomistic spin dynamics simulations. It reveals that thermal activation is crucial for overcoming the energy barrier in the switching process.
Article
Materials Science, Multidisciplinary
Roberto Lo Conte, Maciej Bazarnik, Krisztian Palotas, Levente Rozsa, Laszlo Szunyogh, Andre Kubetzka, Kirsten von Bergmann, Roland Wiesendanger
Summary: In this study, the structural, magnetic, and superconducting properties of single and double atomic layers of Mn on a clean and unreconstructed Nb(110) substrate are investigated. Scanning tunneling spectroscopy measurements at low temperature reveal a proximity-induced superconducting state and in-gap Yu-Shiba-Rusinov bands in the Mn thin films, which grow pseudomorphically on the Nb surface. Spin-polarized scanning tunneling microscopy measurements show a c(2 x 2) antiferromagnetic (AFM) order in the Mn layers, with an out-of-plane spin orientation. First-principles density functional theory calculations confirm the experimentally observed magnetic state, which is understood as the consequence of a strong intralayer and interlayer nearest-neighbor AFM exchange coupling.
Article
Materials Science, Multidisciplinary
Bendeguz Nyari, Andras Laszloffy, Laszlo Szunyogh, Gabor Csire, Kyungwha Park, Balazs Ujfalussy
Summary: This study utilizes a fully relativistic first-principles approach to investigate the spectral properties of magnetic impurities on a superconducting substrate, focusing on the formation of YSR states. Results show that variations in spin-orbit coupling and magnetic fields can lead to the splitting or formation of zero bias peaks in the YSR states under different conditions.
Article
Materials Science, Multidisciplinary
Junlin Wang, Mara Strungaru, Sergiu Ruta, Andrea Meo, Yifan Zhou, Andras Deak, Laszlo Szunyogh, Paul-Iulian Gavriloaea, Roberto Moreno, Oksana Chubykalo-Fesenko, Jing Wu, Yongbing Xu, Richard F. L. Evans, Roy W. Chantrell
Summary: Skyrmions are topologically protected nanoscale magnetic structures with various potential applications. Their lifecycle includes creation, intrinsic dynamics, thermal stability, and eventual thermodynamic demise. Skyrmions can spontaneously form in thermodynamic equilibrium at elevated temperatures, making them suitable for applications like random number generation.
Article
Materials Science, Multidisciplinary
Andrew Ross, Romain Lebrun, Martin Evers, Andras Deak, Laszlo Szunyogh, Ulrich Nowak, Mathias Klaeui
Summary: This study investigates the long-distance transport of thermally generated magnonic spin currents in the insulating antiferromagnetic phase of iron oxide. The research highlights the significant thermal spin transport without the need for net magnetization.
Article
Materials Science, Multidisciplinary
Manuel dos Santos Dias, Sascha Brinker, Andras Laszloffy, Bendeguz Nyari, Stefan Bluegel, Laszlo Szunyogh, Samir Lounis
Summary: Atomistic spin models are valuable for predicting and understanding magnetic properties of materials, and extensions of these models can lead to new physics and applications. Recent studies have uncovered various types of generalized chiral interactions, but some proposed interactions do not comply with basic principles, calling for resolution.
