Article
Chemistry, Physical
Branka Babic-Stojic, Dusan Brankovic, Dusan Milivojevic, Zvonko Jaglicic
Summary: Nanocomposites of magnetic spinel oxide Co1+yAl2-yO4 nanoparticles dispersed in an amorphous SiO2 matrix exhibit spin-glass-like behavior and weak ferromagnetism, attributed to a core-shell structure with the spin-glass phase in the core and weak ferromagnetism in the shell. The observed magnetic properties are explained by the presence of Co vacancies in the nanoparticle spinel crystal lattice.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
P. T. Tho, N. Tran, N. T. M. Hong, N. N. Tran, L. T. Ha, P. T. Phong, D. V. Karpinsky, C. T. A. Xuan
Summary: The external magnetic field is used to control the spin states at the phase boundary in BiFeO3-based ceramics. The spin states can transform from unfrustrated to frustrated under a magnetic field larger than a critical value, leading to an increase in net magnetization during a sweep decrease of magnetic field. The frustrated spin states form a ferromagnetic configuration and interact with intrinsic antiferromagnetic spins, resulting in vertical magnetization shift, field step-dependent hysteresis loop, and training effects. The unique properties of the spin states at the phase boundary allow for control of coercivity and magnetization by magnetic field.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Chemistry, Physical
Chang Woo Kim, In Ho Kim, Young Soo Kang
Summary: A facile strategy for fabricating exchange-coupled nanomagnets with a large energy product was suggested in this study, successfully obtaining a SmCo5/Co nanocomposite magnet through a three-step approach, demonstrating the importance of dimension and arrangement of hard and soft phases for effective magnetic spin exchange interaction.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Physics, Applied
Yinong Yin, Fanfan Shi, Guo-Qiang Liu, Xiaojian Tan, Jun Jiang, Ashutosh Tiwari, Baohe Li
Summary: This study investigates the magnetic properties and magnetocaloric performance of two high-entropy perovskites. It is found that a spin-glass phase occurs at low temperatures in the high-entropy compounds, leading to a sluggish magnetic transition. The increase in configurational entropy results in large refrigerant capacity for these materials.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Andrew D. King, Cristiano Nisoli, Edward D. Dahl, Gabriel Poulin-Lamarre, Alejandro Lopez-Bezanilla
Summary: Artificial spin ices are frustrated spin systems that can be engineered to allow the design and characterization of exotic emergent phenomena. In this study, a realization of spin ice in a lattice of superconducting qubits was reported, showing control over a fragile degeneracy point and the demonstration of Gauss's law for emergent effective monopoles in two dimensions. This qubit control paves the way for potential future study of topologically protected artificial quantum spin liquids.
Article
Chemistry, Physical
Tao Ye, Zhimin Li, Honglin Yan, Yuan Ha, Dongyan Zhang, Chaoyi Zhou, Lijuan Wang, Lu Li, Qianxin Xiang
Summary: This study investigates the role of Mn ions in cobalt-free LiNixMn1-xO2 (NM, x >= 0.5) layered oxides as cathode materials for lithium-ion batteries. It is found that high spin states of Mn ions cause magnetic frustration, aggravating the Li/Ni ionic disorder and hindering Li+ migration, resulting in inferior rate performance.
ADVANCED ENERGY MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Shuxuan Tang, Xinping Wang
Summary: Spin frustration, resulting from geometric frustration and the inability to simultaneously satisfy all antiferromagnetic interactions, is highly important in physics and materials science. Organic radical species, with their flexible chemical structures, show great potential in building spin-frustrated molecules and lattices.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Multidisciplinary Sciences
Xiaoyu Zhang, Ayhan Duzgun, Yuyang Lao, Shayaan Subzwari, Nicholas S. Bingham, Joseph Sklenar, Hilal Saglam, Justin Ramberger, Joseph T. Batley, Justin D. Watts, Daniel Bromley, Rajesh Chopdekar, Liam O'Brien, Chris Leighton, Cristiano Nisoli, Peter Schiffer
Summary: The study demonstrates that Boltzmann-distributed strings of local excitations can describe the topological physics of the Santa Fe geometry, which shows strong correlations and applies to classical systems. Experimental results show that the string length follows a simple Boltzmann distribution with an energy scale related to magnetic interactions and consistent with theoretical predictions.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Condensed Matter
Mouli Roy Chowdhury, Mohindar S. Seehra, Prativa Pramanik, Sayandeep Ghosh, Tapati Sarkar, Bruno Weise, Subhash Thota
Summary: The nature of magnetism in the doubly-diluted spinel ZnTiCoO4 = (Zn2+)( A ) [Ti4+Co2+]( B )O-4 is reported here. The study reveals the spin-glass state in ZnTiCoO4 below the spin glass freezing temperature T (SG) = 12.9 K. The field dependence of T (SG) and the magnetic phase diagram in the H-T plane are established.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Applied
Peter Schiffer, Cristiano Nisoli
Summary: Artificial spin ice systems are arrays of interacting nanoscale magnetic moments with collective behavior, designed based on chosen array geometry. Research in artificial spin ice has expanded beyond the original focus, now encompassing structures exhibiting a wider range of physical phenomena.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Multidisciplinary
Mingxi Yue, Zi Cai
Summary: Studies of systems far from equilibrium are exploring new phases of matter. This study examines a driven-dissipative frustrated spin system, proposing an out-of-equilibrium nonmagnetic phase where spins do not order but adhere to the ice rule in space and establish longrange crystalline order in time. Experimental realizations of the model are discussed.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Ayhan Duzgun, Cristiano Nisoli
Summary: The study proposes the first skyrmion spin ice realized via confined, interacting liquid crystal skyrmions, demonstrating their use as quasiparticles to achieve binary variables that form ice-rule states. This finding not only opens up entirely novel avenues in the field of frustrated systems, but also shows the viability of liquid crystal skyrmions as elementary degrees of freedom in designing collective complex behaviors.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Huda A. Alburaih, Sadia Nazir, Naveed Ahmed Noor, Amel Laref, Ramesh Sharma
Summary: The current study used full-potential methods to investigate the ferromagnetic characteristics of CdTm2Y4(Y= S, Se) spinels. The results revealed the stability of the ferromagnetic state in these materials, as well as their ductile behavior. Additionally, the calculations of thermal stability and thermoelectric efficiency are essential for evaluating the suitability of these materials in waste energy recovery systems and other technological applications.
Article
Chemistry, Multidisciplinary
Ryan A. Murphy, Lucy E. Darago, Michael E. Ziebel, Elizabeth A. Peterson, Edmond W. Zaia, Michael W. Mara, Daniel Lussier, Ever O. Velasquez, David K. Shuh, Jeffrey J. Urban, Jeffrey B. Neaton, Jeffrey R. Long
Summary: The discovery of conductive and magnetic 2D materials, such as the Mn-3(C6S6) metal-organic kagome lattice, represents a versatile route through coordination chemistry. This work demonstrates the potential utility of geometric frustration in the design of new nanoscale spintronic materials, providing a new strategy for engineering exchange bias systems using single-phase, crystalline lattices.
ACS CENTRAL SCIENCE
(2021)
Article
Chemistry, Physical
Pawel Peczkowski, Elzbieta Szostak, Ewa Pochec, Jan Marek Michalik, Jaroslaw Pietosa, Tarek Tahraoui, Maciej Luszczek, Lukasz Gondek
Summary: This paper investigates the mechanisms of tuning the magnetic, electronic, and cytotoxic properties of the CoFe2_xLaxO4 system (x≤0.1) by introducing a small amount of lanthanum ions (La3+). It was found that the main mechanism is the complex exchange interaction between the 3d states of cations and the 2p states of oxygen caused by mixing of the metals over the tetragonal and octahedral positions. The synthesized CoFe2_xLaxO4 nanoparticles (NPs) show high impact on cancer cells while having significantly lower toxicity towards normal cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Physics, Atomic, Molecular & Chemical
A. Alfonsov, B. Buechner, V. Kataev
Summary: The study proposes the use of a cantilever-based setup to overcome challenges posed by small sample sizes, enabling detection of static magnetic response and ESR signal in novel magnetic materials samples.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Morgan C. Allison, Sabine Wurmehl, Bernd Buechner, Joseph L. Vella, Tilo Soehnel, Sascha A. Braeuninger, Hans-Henning Klauss, Maxim Avdeev, Frederick P. Marlton, Siegbert Schmid, Chris D. Ling
Summary: FeMn3Ge2Sn7O16 is a fully ordered stoichiometric phase with an undistorted hexagonal kagome' lattice of Mn2+ cations. By replacing silicon with germanium and anisotropic high-spin Fe2+ with isotropic high-spin Mn2+, the perfection of the kagome lattice is improved, ruling out single-ion anisotropy as the driving force for the unique properties of the compounds.
CHEMISTRY OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Vitaliy Romaka, Ahmad Omar, Wolfgang Loeser, Bernd Buechner, Sabine Wurmehl
Summary: Investigations into the thermodynamic phase diagram of Co-based Heusler phases, focusing on the quaternary region of CoCrCoAl-CoFe, revealed critical points and immiscibility regions through DFT and thermodynamic calculations, offering valuable insights for materials design.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Olga Kataeva, Kamil Ivshin, Kirill Metlushka, Kristina Nikitina, Vera Khrizanforova, Yulia Budnikova, Robert R. Fayzullin, Shamil Latypov, Sandra Schiemenz, Michael Bretschneider, Alexey Popov, Stanislav Avdoshenko, Yulia Krupskaya, Bernd Buchner, Martin Knupfer
Summary: A series of new charge-transfer cocrystals of F(2)TCNQ with anthracene, tetracene, and chrysene were prepared and characterized. The study revealed that face-to-face pi-pi interactions are crucial for the formation of cocrystals, but lateral noncovalent interactions also play a significant role in the supramolecular arrangement and charge transfer. UV/vis spectroscopy and electronic structure quantum chemical calculations classified these cocrystals as small-gap semiconductors with energy gaps of 0.7-1.3 eV.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Nanoscience & Nanotechnology
Daniel Wolf, Sebastian Schneider, Ulrich K. Rossler, Andras Kovacs, Marcus Schmidt, Rafal E. Dunin-Borkowski, Bernd Buechner, Bernd Rellinghaus, Axel Lubk
Summary: Holographic vector-field electron tomography quantitatively reconstructed the three-dimensional magnetic texture of Bloch skyrmion tubes in FeGe with sub-10-nanometre resolution, revealing complex three-dimensional modulations and fundamental principles of skyrmion formation.
NATURE NANOTECHNOLOGY
(2022)
Article
Chemistry, Physical
M. A. Belyanchikov, Z. Bedran, M. Savinov, P. Bednyakov, P. Proschek, J. Prokleska, V. A. Abalmasov, E. S. Zhukova, V. G. Thomas, A. Dudka, A. Zhugayevych, J. Petzelt, A. S. Prokhorov, V. B. Anzin, R. K. Kremer, J. K. H. Fischer, P. Lunkenheimer, A. Loidl, E. Uykur, M. Dressel, B. Gorshunov
Summary: This study investigates the collective modes and single-particle excitations of water molecules confined within nanocages using comprehensive broad-band dielectric spectroscopy, specific heat studies, and molecular dynamics and Monte Carlo simulations. The results show that the confined water molecules exhibit rich anisotropic temperature-dependent excitations, and a ferroelectric order-disorder phase transition is confirmed at approximately 3 K.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Julian Wagner, Anuja Sahasrabudhe, Rolf B. Versteeg, Lena Wysocki, Zhe Wang, Vladimir Tsurkan, Alois Loidl, Daniel Khomskii, Hamoon Hedayat, Paul H. M. van Loosdrecht
Summary: The evolution of the zigzag order parameter in alpha-RuCl3 is studied, revealing the presence of metamagnetic transitions and the emergence of an intermediate phase induced by a magnetic field. The results provide a quantitative description of the bond-anisotropic interactions in alpha-RuCl3.
NPJ QUANTUM MATERIALS
(2022)
Article
Physics, Multidisciplinary
Peter Lunkenheimer, Alois Loidl, Birte Riechers, Alessio Zaccone, Konrad Samwer
Summary: The Lindemann criterion applies to the melting of crystals but not to glasses. There is a universal relationship between glass temperature and thermal expansion. The thermal expansion coefficient of glasses behaves differently from crystals, indicating a liquid-solid cross-over in glasses.
Article
Chemistry, Physical
P. Lunkenheimer, A. Loidl, G. P. Johari
Summary: By using dielectric spectroscopy, we investigated dipolar relaxations, dc conductivity, and polar order in AgCN. The conductivity contribution dominates at high temperatures and low frequencies, originating from silver ions' mobility. We observed dipolar relaxation of CN- ions and found a phase with quadrupolar order in AgCN, indicating dipolar head-to-tail disorder of the CN- ions at elevated temperatures. Under about 475 K, a long-range polar order of the CN dipole moments emerges.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Verena Schiller, Katharina Knippen, Alois Loidl, Peter Lunkenheimer, Dirk Volkmer, Michael Vogel
Summary: We used H-2 nuclear magnetic resonance (NMR) to investigate the reorientation and diffusion of water in the metal-organic framework MFU-4l. The study revealed that the rotational correlation times follow different relations above and below certain temperatures, with a continuous evolution in between. The NMR results were consistent with previous broadband dielectric spectroscopy (BDS) data on water in a similar framework. The water dynamics at low temperatures did not fully restore ergodicity, suggesting the presence of spatially heterogeneous water properties.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
K. L. Ngai, S. Capaccioli, P. Lunkenheimer, A. Loidl
Summary: This paper critically compares four major interpretations to identify the most plausible interpretation of the relaxation processes observed in the dielectric spectra of glycerol.
Article
Chemistry, Physical
Julian Wagner, Anuja Sahasrabudhe, Rolf Versteeg, Zhe Wang, Vladimir Tsurkan, Alois Loidl, Hamoon Hedayat, Paul H. M. van Loosdrecht
Summary: We have conducted time-resolved magneto-optical spectroscopy on the magnetic Mott-Hubbard-insulating Kitaev spin liquid candidate α-RuCl3 to investigate the non-equilibrium dynamics of its antiferromagnetically ordered zigzag groundstate after photoexcitation. Our findings reveal the dynamical interplay of charge excitations with the zigzag ordered state on ultrashort time scales, and the existence of a long-lived non-thermal antiferromagnetic spin-disordered state. These results have implications for the study of nonequilibrium states in strongly correlated materials.
FARADAY DISCUSSIONS
(2022)
Article
Materials Science, Multidisciplinary
J. Arneth, M. Jonak, S. Spachmann, M. Abdel-Hafiez, Y. O. Kvashnin, R. Klingeler
Summary: In quasi-two-dimensional layered van der Waals material CrI3, the ferromagnetic ordering temperature is studied experimentally to show that compression along the c axis increases intralayer magnetic coupling, while negative in-plane strain decreases it. Interlayer exchange initially increases and subsequently decreases upon the application of both out-of-plane and in-plane compression.
Article
Materials Science, Multidisciplinary
F. Bougamha, S. Selter, Y. Shemerliuk, S. Aswartham, A. Benali, B. Buechner, H-J Grafe, A. P. Dioguardi
Summary: We report the anomalous breakdown in the scaling of the microscopic magnetic susceptibility with the bulk magnetic susceptibility in Mn2P2S6. NMR spectra provide evidence for domain rotation and spin-flop transition in the magnetic state. A spin-flop-induced splitting of the NMR spectra is observed in Ni2P2S6.
Article
Materials Science, Multidisciplinary
Anirudha Ghosh, D. Singh, T. Aramaki, Qingge Mu, V Borisov, Y. Kvashnin, G. Haider, M. Jonak, D. Chareev, S. A. Medvedev, R. Klingeler, M. Mito, E. H. Abdul-Hafidh, J. Vejpravova, M. Kalbac, R. Ahuja, Olle Eriksson, Mahmoud Abdel-Hafiez
Summary: By advanced experimental techniques and theoretical calculations, we have investigated the pressure-temperature phase diagram of CrI3 single crystals and found that pressure can effectively control the magnetic and electrical properties of this material. Pressure reduces the ordering temperature of CrI3 and induces a transition from ferromagnetism to antiferromagnetism, as well as a phase transition from semiconductor to metal.
