Article
Materials Science, Multidisciplinary
Y. Kamiya
Summary: The frustrated triangular Ising magnet Ca3Co2O6 is characterized by extremely slow spin dynamics and peculiar magnetic orders. A field-cooling protocol was proposed to bypass the low-field SDW phase and investigate the connection between slow relaxation and cooling process. Monte Carlo simulations were used to map out the equilibrium in-field phase diagram and Ginzburg-Landau theory explained the observed magnetic field induced deformation of the SDW microphases.
Article
Materials Science, Multidisciplinary
Santanu De, Amit Chauhan, B. R. K. Nanda, A. Banerjee
Summary: The Ising magnetism in the CCO system is attributed to the large contribution of orbital moment to magnetization and strong magnetocrystalline anisotropy. The study reveals the role of spin-orbit coupling and crystal-field effects in this Ising character of magnetism through the temperature and field dependence of magnetization in the presence of hydrostatic pressures. The interplay of trigonal crystal-field and spin-orbit coupling effects is further demonstrated through a quantitative analysis of field-dependent magnetization.
Article
Chemistry, Inorganic & Nuclear
Davor L. Mariano, Dalber Ruben S. Candela, Daniele C. Freitas, AlgurioZ. Trujillo, Edson C. Passamani, Mucio A. Continentino, Luis Ghivelder
Summary: Below 42 K, the homometallic Co3O2BO3 ludwigite forms magnetic planes separated by nonmagnetic low-spin Co3+ ions. The substitution of Co3+ by other nonmagnetic ions enhances the magnetic interactions, raising the magnetic ordering temperature. However, depending on the nonmagnetic dopant ion, the remaining Co3+ ions could adopt a high-spin state, creating magnetic frustration and lowering the magnetic transition temperature. Doping Co3O2BO3 with nonmagnetic In3+ ions favors the appearance of both high-spin Co2+ and Co3+.
INORGANIC CHEMISTRY
(2023)
Article
Physics, Multidisciplinary
Kira Riedl, Elena Gati, David Zielke, Steffi Hartmann, Oleg M. Vyaselev, Nataliya D. Kushch, Harald O. Jeschke, Michael Lang, Roser Valenti, Mark Kartsovnik, Stephen M. Winter
Summary: Organic salts provide an ideal experimental platform for studying the interplay between magnetic and charge degrees of freedom, with recent research on kappa-(BETS)2Mn[N(CN)2]3 (kappa-Mn) confirming the importance of ring exchange and supporting the proposed chiral spin-liquid scenario for triangular lattice organics.
PHYSICAL REVIEW LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Mantao Huang, Muhammad Usama Hasan, Konstantin Klyukin, Delin Zhang, Deyuan Lyu, Pierluigi Gargiani, Manuel Valvidares, Sara Sheffels, Alexandra Churikova, Felix Buettner, Jonas Zehner, Lucas Caretta, Ki-Young Lee, Joonyeon Chang, Jian-Ping Wang, Karin Leistner, Bilge Yildiz, Geoffrey S. D. Beach
Summary: Voltage control of magnetic order is essential for energy-efficient spintronic applications, and solid-state hydrogen gating allows for reversible ferrimagnetic order control, external-field-free 180 degrees magnetic switching, and ferrimagnetic spin texture manipulation. In this study, the use of electric field-induced hydrogen loading/unloading in GdCo shifts the magnetic compensation temperature and enables control of the dominant magnetic sublattice. Additionally, the weakening of antiferromagnetic exchange coupling results in reversible gate voltage-induced net magnetization switching and generation of ferrimagnetic spin textures.
NATURE NANOTECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Yusuf Yuksel, Umit Akinci, Erol Vatansever
Summary: Using the effective-field theory, this study investigates the dynamic behavior of a kinetic spin -S Blume Capel model and evaluates its phase diagrams. The results show the emergence of metamagnetic anomalies in the dynamic susceptibility versus bias field curves within a specific range of the bias field. The relationship between susceptibility and bias field exhibits a linear variation, indicating the asymptotic approach of the oscillating field amplitude in the slow critical dynamics regime. Furthermore, the findings suggest that recent discoveries regarding the dynamic Ising model also apply to the kinetic Blume-Capel model with arbitrary spin.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Article
Nanoscience & Nanotechnology
N. Biniskos, F. J. dos Santos, M. dos Santos Dias, S. Raymond, K. Schmalzl, P. Steffens, J. Persson, N. Marzari, S. Bluegel, S. Lounis, T. Brueckel
Summary: In this study, we investigate the spin-excitation spectrum of bulk Mn5Si3 using inelastic neutron scattering measurements and density functional theory calculations. We find that the spin dynamics of each phase in Mn5Si3 is robust against any combination of temperature and magnetic field. The high-energy spin dynamics exhibit distinctive characteristics of either spin waves or broad fluctuation patterns in different phases.
Article
Chemistry, Multidisciplinary
Dmitry Yu Aleshin, Rosa Diego, Leoni A. Barrios, Yulia Nelyubina, Guillem Aromi, Valentin V. Novikov
Summary: The study successfully observed the dynamics of two rare spin states, opening up new possibilities for information storage and processing.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Materials Science, Multidisciplinary
A. B. Van'kov, A. S. Koreyev, P. S. Berezhnoy, I. V. Kukushkin
Summary: Offbeat spin textures are observed in strongly correlated quantum Hall ferromagnets, suggesting a breakdown of spin-rotational symmetry in the ground state. These textures involve the orbital degree of freedom and are qualitatively different from ordinary skyrmions.
Article
Nanoscience & Nanotechnology
Cory D. Cress, Darshana Wickramaratne, Matthew R. Rosenberger, Zachariah Hennighausen, Patrick G. Callahan, Samuel W. LaGasse, Noam Bernstein, Olaf M. van 't Erve, Berend T. Jonker, Syed B. Qadri, Joseph C. Prestigiacomo, Marc Currie, Igor I. Mazin, Steven P. Bennett
Summary: In this work, we demonstrate the direct writing of nanoscale magnetic ordering patterns in FeRh films using focused helium-ion beam irradiation. By characterizing the changes in magnetic order induced by He+ irradiation, as well as quantifying strain- and defect-induced alterations in spin-flip energy, we show promise for the development of in-plane AF-FM spintronic devices. This approach may reduce the complexity of fabrication processes and eliminate interfacial polarization losses in such devices.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Inorganic & Nuclear
Qi Zhao, Jin-Peng Xue, Zhi-Kun Liu, Zi-Shuo Yao, Jun Tao
Summary: A mononuclear complex with long alkyl chains was synthesized, showing incomplete one-step spin crossover in magnetic measurements. Various methods, including changing scanning rate, sample annealing, and light irradiation, were used to effectively improve the completeness of spin crossover.
DALTON TRANSACTIONS
(2021)
Article
Materials Science, Multidisciplinary
G. R. Hoogeboom, T. Kuschel, G. E. W. Bauer, M. Mostovoy, A. Kimel, B. J. van Wees
Summary: This study investigates spin Hall magnetoresistance and spin Seebeck effect in a rare-earth antiferromagnetic DyFeO3 single crystal with a thin Pt film contact. The experimental results reveal the unique properties of SMR and SSE in this material, providing insight into spin reorientation phase transitions and sublattice magnetizations. Overall, the combination of SMR and SSE proves to be a simple and efficient tool for studying magnetic phenomena in materials.
Article
Nanoscience & Nanotechnology
Yong Guo, Tingting Zhang, Zhishuo Zhang, Bin Chen, Wenhui Guo, Shuang Pan, Yong Gong, Yuqing Bai, Yuanyuan Gong, Jun Liu, Xuefei Miao, Feng Xu
Summary: In this work, a six-component MnFeCoNiGeSi high-entropy system is designed, exhibiting low-hysteresis magnetostructural transformation and a large magnetocaloric effect. By increasing the configurational entropy, the alloy almost completely transforms into the orthorhombic structure and shows reversible magnetic-field-induced magnetostructural transformation. This study is of great significance for the research on the magnetic and thermal properties of high-entropy alloys.
Article
Physics, Condensed Matter
Pralay Paul, A. K. Rajarajan, P. D. Babu, T. V. Chandrasekhar Rao
Summary: Our study on the polycrystalline GdFeO3 compound revealed an antiferromagnetic transition associated with Gd3+ spins and a spin-flop type metamagnetic transition linked to Gd3+ sub lattice. Additionally, weak hysteresis behavior related to canted Fe3+ moments near-zero field region was observed, with a remnant magnetization of around 0.022 mu(B).
SOLID STATE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Charlotte Pughe, Otto H. J. Mustonen, Alexandra S. Gibbs, Stephen Lee, Rhea Stewart, Ben Gade, Chennan Wang, Hubertus Luetkens, Anna Foster, Fiona C. Coomer, Hidenori Takagi, Edmund J. Cussen
Summary: Ba2CuTeO6 is a material with a two-leg spin ladder structure of Cu2+ cations, which can be chemically tuned by substituting non-magnetic Zn2+ at the Cu2+ site. The substitution partitions the spin ladders into clusters, leading to a transition from long-range order to spin-freezing as the Zn2+ substitution increases. This provides a well-controlled tuning of the magnetic disorder and a model system for studying defects and segmentation in low-dimensional quantum magnets.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Manpreet Kaur, Marc Walker, Steven Hindmarsh, Charlotte Bolt, Stephen York, Yisong Han, Martin R. Lees, Katharina Brinkert
Summary: Efficient artificial photosynthesis systems use catalyst- and surface-functionalized photovoltaic devices to perform photoelectrochemical water oxidation, CO2 recycling, and hydrogen generation. This research focuses on developing photoelectrodeposition procedures to directly deposit mixed-metal electrocatalyst nanostructures on semiconductor surfaces for light-assisted dinitrogen activation. The electrocatalyst films fabricated through this process exhibit different physical properties and are largely nitrogen-free, which is challenging to achieve using traditional deposition techniques. Initial measurements and XPS studies confirm the successful activation of dinitrogen using these electrocatalyst coatings.
FARADAY DISCUSSIONS
(2023)
Article
Multidisciplinary Sciences
Christopher Klose, Felix Buettner, Wen Hu, Claudio Mazzoli, Kai Litzius, Riccardo Battistelli, Ivan Lemesh, Jason M. Bartell, Mantao Huang, Christian M. Guenther, Michael Schneider, Andi Barbour, Stuart B. Wilkins, Geoffrey S. D. Beach, Stefan Eisebitt, Bastian Pfau
Summary: Nanoscale magnetic fluctuations are observed beyond conventional resolution limits using coherent correlation imaging, allowing for the study of previously inaccessible magnetic phenomena. The method utilizes Fourier space analysis and an iterative hierarchical clustering algorithm to achieve high spatial and temporal resolution.
Article
Chemistry, Multidisciplinary
Stephen E. Brown, Ioanna Mantaloufa, Ryan T. Andrews, Thomas J. Barnes, Martin R. Lees, Frank De Proft, Ana V. Cunha, Sebastian D. Pike
Summary: The molecular titanium-oxo cluster [Ti6O6((OPr)-Pr-i)(6)((O2CBu)-Bu-t)(6)] (1) can be activated by UV light to produce a mixed valent (photoreduced) Ti (iii/iv) cluster, along with alcohol and ketone organic products. Mechanistic studies show a two-electron mechanism utilizing the cluster structure for multielectron reactions. The photoreduced products [Ti6O6((OPr)-Pr-i)(4)((O2CBu)-Bu-t)(6)(sol)(2)] can be isolated and characterized, and undergo onward oxidation under air. The redox reactivity described is only possible in a cluster with multiple Ti sites.
Article
Chemistry, Multidisciplinary
Robyn E. Powell, Martin R. Lees, Graham J. Tizzard, Simon J. Coles, Qingchun Yuan, Petra J. van Koningsbruggen
Summary: The synthesis and crystal structure (100 K) of the compound [(CH3)(2)NH2]-[Fe(C10H11O2N3S)(2)] are reported. The structure consists of an octahedral [Fe-III (L)(2)](-) fragment and a dimethylammonium cation. Each L2- ligand binds to the FeIII ion through the S, N, and O atoms, forming an (FeS2N2O2)-S-III chromophore. The ligands are arranged in two perpendicular planes, with the O and S atoms in cis positions and the N atoms in trans positions. The magnetic measurements confirm the presence of a high-spin Fe-III ion with D = 0.83 (1) cm(-1) and g = 2 at 100 K.
ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Nelson Hua, Jianheng Li, Stjepan B. Hrkac, Andi Barbour, Wen Hu, Claudio Mazzoli, Stuart Wilkins, Roopali Kukreja, Eric E. Fullerton, Oleg G. Shpyrko
Summary: We studied charge-orbital fluctuations in the insulating state of magnetite using resonant elastic x-ray scattering and x-ray photon correlation spectroscopy. Our results revealed the dynamics of the iron 3d and oxygen 2p orbital domains, showing a decoupling of the orbital correlation lengths between the oxygen ligands and site-specific iron 3d states. We also observed charge-orbital domain fluctuations at the iron t(2g) orbital sites of trimeron chains.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Engineering, Environmental
Sayan Pal, Maximilian O. Besenhard, Liudmyla Storozhuk, Martin R. Lees, Nguyen Thi Kim Thanh, Asterios Gavriilidis
Summary: This work demonstrates a modular triphasic flow reactor platform that enables continuous and fouling-free four-step co-precipitation flow synthesis of iron oxide nanoparticles (IONPs) for magnetically induced hyperthermia cancer treatment (MHCT). By using a seeded growth co-precipitation strategy and a nitrogen gas spacer, the flow platform allows for the continuous synthesis of colloidally stable IONPs with high heating performance in a short residence time.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Lu Jia, Matthew D. Lloyd, Martin R. Lees, Limin Huang, Richard I. Walton
Summary: In this study, the crystallization of a new series of A-site substituted lanthanum ferrite materials (La1-xREx)FeO3 was explored using hydrothermal method. The effect of elemental substitution on the morphological, structural, and magnetic properties of the materials was studied. It was found that homogeneous solid solutions are formed when La3+ and substituent ions have similar radii, while crystallization in separate phases is found when there is a large radius difference. A-site replacement induces an evolution in the crystallite shape, providing evidence for a phase-separation-driven evolution of morphology.
INORGANIC CHEMISTRY
(2023)
Correction
Multidisciplinary Sciences
Christopher Klose, Felix Buttner, Wen Hu, Claudio Mazzoli, Kai Litzius, Riccardo Battistelli, Sergey Zayko, Ivan Lemesh, Jason M. M. Bartell, Mantao Huang, Christian M. Guenther, Michael Schneider, Andi Barbour, Stuart B. B. Wilkins, Geoffrey S. D. Beach, Stefan Eisebitt, Bastian Pfau
Article
Multidisciplinary Sciences
E. Garlatti, A. Albino, S. Chicco, V. H. A. Nguyen, F. Santanni, L. Paolasini, C. Mazzoli, R. Caciuffo, F. Totti, P. Santini, R. Sessoli, A. Lunghi, S. Carretta
Summary: Understanding phonon-induced relaxation in molecular qubits is crucial for their application potential. Garlatti et al. utilize inelastic X-ray scattering and density functional theory to investigate the role of low-energy phonons on spin relaxation in a prototypical molecular qubit. They find that intra-molecular vibrations with very-low energies are largely responsible for spin relaxation up to ambient temperature. This research provides insights into improving spin coherence and opens new avenues for the investigation of magnetic molecules for quantum devices.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Amelia E. Hall, Pascal Manuel, Dmitry D. Khalyavin, Fabio Orlandi, Daniel A. Mayoh, Lieh-Jeng Chang, Yu-Sheng Chen, David G. C. Jonas, Martin R. Lees, Geetha Balakrishnan
Summary: The Mn3XY family of materials, with ordered chiral beta-Mn structure, displays different magnetic behaviors, with Mn3RhGe exhibiting a high-temperature incommensurate magnetic structure transitioning into a noncollinear commensurate antiferromagnetic ground state, while Mn3IrSi shows a noncollinear commensurate magnetic structure at all temperatures.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
G. D. A. Wood, D. D. Khalyavin, D. A. Mayoh, J. Bouaziz, A. E. Hall, S. J. R. Holt, F. Orlandi, P. Manuel, S. Bluegel, J. B. Staunton, O. A. Petrenko, M. R. Lees, G. Balakrishnan
Summary: We investigate the magnetic structure of GdRu2Si2 using neutron diffraction and discover higher-order magnetic satellites. We refine a double-Q constant-moment model using powder diffraction and find that the structure contains vortexlike motifs with a one-dimensional topological charge density.
Article
Materials Science, Multidisciplinary
Ashish Kumar Mishra, S. Shanmukharao Samatham, Mark T. F. Telling, A. D. Hillier, Martin R. Lees, K. G. Suresh, V. Ganesan
Summary: We have observed the presence of magnetic rare regions in Fe-doped MnSi that exhibit the quantum Griffiths phase. These rare regions exhibit slow dynamics at low temperatures, resulting in non-Fermi-liquid behavior in heat capacity and magnetization. Our μSR and magnetization measurements indicate that the dynamics freeze into a cluster-glass state below Tf around 1.25 K. These findings are consistent with theoretical models proposed for metallic systems with Heisenberg symmetry and strong disorder exhibiting the quantum Griffiths phase.
Article
Physics, Multidisciplinary
Jonathan Frassineti, Pietro Bonfa, Giuseppe Allodi, Erick Garcia, Rong Cong, Brenden R. Ortiz, Stephen D. Wilson, Roberto De Renzi, Vesna F. Mitrovic, Samuele Sanna
Summary: The recently discovered vanadium-based Kagome metals AV3Sb5 exhibit a unique phase transition into charge-density wave (CDW) order that occurs before unconventional superconductivity and time-reversal symmetry breaking. To understand the role of CDW in establishing these unconventional phases, it is crucial to unveil the symmetries and microscopic nature of the charge-ordered phase. In this study, the exact structure of the charge-density wave ordering temperature (TCDW) below RbV3Sb5 is determined through a comprehensive set of nuclear magnetic resonance (NMR) measurements and density functional theory simulations. The findings provide important guidance for developing a theoretical framework to predict properties of exotic electronic orders within the CDW phase.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Wilgner Lima da Silva, Ashok S. Menon, Martin R. Lees, Reza J. Kashtiban, Marc Walker, Louis F. J. Piper, Emma Kendrick, Richard I. Walton
Summary: A Mn2+-Li-Nb disordered rock-salt oxide cathode is prepared by a solid-state reaction under 5% H-2/N-2 atmosphere, showing a high voltage plateau and irreversible structural changes in the first cycle.
CHEMICAL COMMUNICATIONS
(2023)
Article
Physics, Atomic, Molecular & Chemical
Murari Soundararajan, George R. Bacanu, Francesco Giustiniano, Mark C. Walkey, Gabriela Hoffman, Marina Carravetta, Martin R. Lees, Richard J. Whitby, Malcolm H. Levitt
Summary: This article presents a new variant of the superconducting fulleride Rb3C60, with He-3 atoms encapsulated in the C-60 cages. The characteristics of the superconducting and normal states are examined using He-3 NMR. Evidence is found for the coexistence of vortex liquid and vortex solid phases below the superconducting transition temperature. The spin-lattice relaxation time constant in the superconducting state shows a strong dependence on spectral frequency, which is revealed by two-dimensional NMR using an inverse Laplace transform. Surprisingly, this phenomenon persists, in attenuated form, at temperatures well above the superconducting transition.
APPLIED MAGNETIC RESONANCE
(2023)