Article
Physics, Multidisciplinary
Jin-Qun Zhong, Zhen-Wei Yu, Xiao-Yu Yue, Yi-Yan Wang, Hui Liang, Yan Sun, Dan-Dan Wu, Zong-Ling Ding, Jin Sun, Xue-Feng Sun, Qiu-Ju Li
Summary: High-quality single crystals of LnCu(3)(OH)(6)Br-3 (Ln = Nd, Sm, and Eu) were grown by hydrothermal method to investigate the effects of lanthanide ions on geometrically frustrated antiferromagnets and their magnetic properties. Crystal structures and magnetic properties were studied, revealing a Kapellasite-type layer structure and strong antiferromagnetic coupling with pronounced magnetic frustration effect. Magnetization measurements showed canted antiferromagnetic ordering of Cu2+ ions within the kagome plane around 16 K and weak ferromagnetic coupling, while shoulder-like anomalies in specific heat indicated the emergence of magnetic ordering. The low-temperature negative magnetization and specific heat of LnCu(3)(OH)(6)Br-3 (Ln = Nd, Sm, and Eu) suggested more exotic magnetic ground state properties induced by Ln (3+) ions.
Article
Materials Science, Multidisciplinary
Leonardo S. Lima
Summary: This study investigates the thermodynamic quantities, such as entropy, specific heat, and magnetic susceptibility, in the next-nearest-neighbors Heisenberg model on a honeycomb-kagome lattice. The linear spin-wave approach is applied to obtain the temperature-dependent behavior of these quantities. Additionally, the entanglement negativity, a quantifier of quantum entanglement, and the spin Hall conductivity are also studied. The results show that all the thermodynamic quantities, as well as the entanglement negativity and spin Hall conductivity, exhibit an increasing trend with temperature. Furthermore, it is found that all the analyzed quantities approach zero in the low-temperature limit, consistent with experimental observations.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2024)
Article
Chemistry, Inorganic & Nuclear
Bachchar Hadrane, Philippe Deniard, Nicolas Gautier, Michael Paris, Christophe Payen, Remi Dessapt
Summary: Pure micro- and nanocrystalline powders of layered-kagome zinc orthovanadate BaZn3(VO4)(2)(OH)(2) have been successfully prepared and characterized. The structures and distributions of the micro- and nanostructured samples have been determined through X-ray diffraction and transmission electron microscopy. The optical properties of the material are also influenced by the nanostructuring.
DALTON TRANSACTIONS
(2023)
Article
Materials Science, Multidisciplinary
Hong Li, Tao Li
Summary: The extreme frustration in the kagome antiferromagnet allows for the realization of numerous closely competing magnetic phases. Through simulation and calculation, it has been found that in a certain region, there is a competition between q = 3 and q = 4 Potts order, which cannot be explained by the conventional order-by-disorder mechanism. This region may host a nematic spin liquid ground state with an anisotropic ring structure.
Article
Physics, Multidisciplinary
M. Semjan, M. Zukovic
Summary: In this study, the possibility of long-range ordering in a vertically stacked kagome lattice of Ising antiferromagnets was investigated. Unlike other systems, no long-range ordering was observed in this model, making it a rare example of a disordered Ising paramagnet composed of frustrated layers coupled by unfrustrated interaction.
Article
Materials Science, Multidisciplinary
M. Mohylna, J. Busa, M. Zukovic
Summary: This study investigates the formation and evolution of the SkX phase in a frustrated antiferromagnetic model on a triangular lattice with DMI, finding that even relatively small DMI intensity can lead to the appearance of the SkX phase. By using the parallel tempering Monte Carlo algorithm, the efficiency of locating phase boundaries between different phases separated by large or barely detectable energy barriers is demonstrated, which is particularly useful for strong first-order transitions.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
M. Mohylna, M. Zukovic
Summary: In this study, we investigated the effects of single-ion anisotropy on the phase diagram topology and the stability of the skyrmion lattice (SkX) phase in a frustrated antiferromagnetic Heisenberg model on a triangular lattice with Dzyaloshinskii-Moriya interaction (DMI) under an external magnetic field. Phase diagrams were constructed for different strengths of easy-axis and easy-plane anisotropy using parallel tempering Monte Carlo simulations. It was found that the SkX phase can be stabilized within a certain temperature and field range, and both types of anisotropy can have beneficial effects on its stabilization. Metropolis dynamics simulations were also performed to investigate the persistence of the SkX phase. It was confirmed that low temperatures, small DMI, and small easy-plane anisotropy values can increase the lifetime of the skyrmions.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Tomonari Mizoguchi, Yoshihito Kuno, Yasuhiro Hatsugai
Summary: The study reveals characteristic band structures of fermions on a square kagome lattice, including flat bands and two spin-1 Dirac cones. Additionally, in the presence of an external field, the profile of the Chern numbers around the modified spin-1 Dirac cones coincides with the conventional one.
Article
Chemistry, Physical
Jem Valerie Perez, Maurice Sorolla, Xiqu Wang, Allan J. Jacobson
Summary: This study presents the synthesis of a new transition metal-based compound with a unique topology, and magnetic and heat capacity measurements indicate special magnetic properties of the Co-II-based compound.
CHEMISTRY OF MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Mingfang Shu, Weicen Dong, Jinlong Jiao, Jiangtao Wu, Gaoting Lin, Yoshitomo Kamiya, Tao Hong, Huibo Cao, Masaaki Matsuda, Wei Tian, Songxue Chi, Zhongwen Ouyang, Hongwei Chen, Youming Zou, Zhe Qu, Qing Huang, Haidong Zhou, Jie Ma
Summary: In this study, we investigated the ground state and spin excitations in Ba3MnSb2O9, an easy-plane S = 5/2 triangular lattice antiferromagnet. Through various techniques including single-crystal neutron scattering, electric spin resonance, and spin wave calculations, we determined the spin Hamiltonian parameters describing the material. We found that Ba3MnSb2O9 is a nearly ideal triangular lattice antiferromagnet with quasiclassical spin S = 5/2, making it a potential candidate for the study of Z- or Z2-vortex excitations.
Article
Physics, Condensed Matter
R. L. Rodriguez-Suarez, S. M. Rezende
Summary: This study investigates antiferromagnetic materials with kagome spin lattices using spin-wave calculations, providing exact analytical expressions for the frequencies of magnons. Experimental data suggests that field parameters obtained from measured frequencies are in agreement with theoretical calculations.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Materials Science, Multidisciplinary
F. A. Kassan-Ogly
Summary: The spontaneous magnetization of the Kagome lattice in the Ising model is thoroughly investigated, and the fallacy of spontaneous magnetization obtained earlier is proven. The exact expression for spontaneous magnetization in the anisotropic case on the Kagome lattice is presented. The frustration properties of the Ising model on 2D Kagome lattice and the explanation of properties of 3D Kagome materials based on theoretical results are comprehensively studied.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ali Frotanpour, Justin Woods, Barry Farmer, Amrit P. Kaphle, J. Todd Hastings, Lance E. DeLong
Summary: The angular dependence of ferromagnetic resonance (FMR) spectra for Fibonacci-distorted, kagome artificial spin ice has been measured, showing that the number of strong modes and discontinuities in the FMR field-frequency dispersion curves depend on the orientation of the applied DC magnetic field. These results suggest that the orientation of the applied magnetic field and severity of Fibonacci distortion serve as control variables for FMR modes and multistep reversal in future magnonic devices and magnetic switching systems.
Article
Materials Science, Multidisciplinary
Johannes Richter, Oleg Derzhko, Juergen Schnack
Summary: Over the last decade, the interest in the spin-1/2 Heisenberg antiferromagnet (HAF) on the square kagome lattice has been growing. This model system is a prominent example of quantum magnetism with a quantum paramagnetic ground state, flat-band physics near the saturation field, and quantum scars. Recent numerical investigations have revealed a gapless spin liquid in the square kagome magnet. The study also provides insights into specific heat, entropy, and susceptibility, revealing low-temperature shoulder below the major maximum and a change in curvature just at a specific temperature, attributed to low-lying singlet excitations and the singlet-triplet gap.
Article
Materials Science, Multidisciplinary
Ellen Fogh, Otto Mustonen, Peter Babkevich, Vamshi M. Katukuri, Helen C. Walker, Lucile Mangin-Thro, Maarit Karppinen, Simon Ward, Bruce Normand, Henrik M. Ronnow
Summary: We investigate the influence of randomness and magnetic frustration in the series of S = 1/2 Heisenberg square-lattice compounds Sr2CuTe1???xWxO6. By substituting W for Te, the magnetic interactions are dramatically altered from nearest-neighbor to next-nearest-neighbor antiferromagnetic coupling. Neutron scattering measurements are performed to study the magnetic ground state and excitations for different x values. A bond-disorder model is proposed to explain the ground states with short-ranged spin correlations in the mixed compounds. The calculated neutron diffraction patterns and powder spectra agree well with the experimental data.
Article
Physics, Multidisciplinary
Pharit Piyawongwatthana, Daisuke Okuyama, Kazuhiro Nawa, Kittiwit Matan, Taku J. Sato
Summary: In this study, the crystal structure of alpha-Cu2V2O7 was revisited and an absolute structure determination was performed. The inclusion of inversion domain was evaluated, and all measured crystals showed zero Flack parameters within standard uncertainty. The relative intensity ratios confirmed the single polar domain nature of alpha-Cu2V2O7 in bulk Bridgman-grown centimeter-sized crystal.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Physics, Multidisciplinary
Hironori Yamaguchi, Taiki Okita, Yoshiki Iwasaki, Yohei Kono, Yuko Hosokoshi, Takanori Kida, Akira Matsuo, Takashi Kawakami, Masayuki Hagiwara
Summary: The magnetic properties of a mixed spin-(1/2, 5/2) chain in a charge-transfer salt were investigated, confirming the formation of the chain and observing a clear LM magnetization plateau. The magnetic susceptibility and specific heat further confirmed the formation of the LM ferrimagnetic state.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Materials Science, Multidisciplinary
H. Tsukiyama, S. Morota, S. Shimono, Y. Iwasaki, M. Hagiwara, Y. Hosokoshi, H. Yamaguchi
Summary: This study successfully synthesized two complexes based on verdazyl and investigated their magnetic properties. The results revealed the unconventional spin structures and electronic properties, proposing an effective method for spin arrangement design.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Physics, Multidisciplinary
Satoshi Morota, Yoshiki Iwasaki, Masayuki Hagiwara, Yuko Hosokoshi, Hironori Yamaguchi
Summary: A Co2+ ion based verdazyl-based complex was successfully synthesized and it was found that there is threefold periodicity of intermolecular and intramolecular interactions between the ligand radicals and the Co ion. Further investigation revealed the Co2+ ion has effective spin-1/2 with anisotropic g values and Ising-like exchange interactions.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Materials Science, Multidisciplinary
H. Yamaguchi, Y. Tominaga, A. Matsuo, S. Morota, Y. Hosokoshi, M. Hagiwara, K. Kindo
Summary: We successfully synthesized a verdazyl-based complex, (p-Py-V-p-F)2[Co(hfac)2]. Molecular-orbital calculations revealed that the complex forms a ladder-based two-dimensional (2D) spin model, where spin ladders composed of radical spins are coupled to Co spins via intramolecular interactions. The complex showed paramagnetic behavior associated with Co spins and a 3/5 magnetization plateau, indicating a rung-singlet-like ground state with fully polarized Co spins. The peculiar behavior of the linear magnetization curve after the magnetization plateau is attributed to a quantum phase transition from a gapped quantum state to a 2D magnetic state.
Article
Materials Science, Multidisciplinary
Hironori Yamaguchi, Hiroki Takahashi, Takashi Kawakami, Kiyomi Okamoto, Toru Sakai, Takeshi Yajima, Yoshiki Iwasaki
Summary: We introduce an organic compound that undergoes a spin-Peierls (SP) transition to form an effective spin-1 antiferromagnetic uniform chain called the Haldane chain. This transition is accompanied by a structural phase transition and the disappearance of magnetization, which can be explained by deforming the compound to an effective spin-1 Haldane chain. The molecular orbitals in this compound are flexible enough to transform the exchange interactions into different topologies of the Haldane state. This SP transition in the compound demonstrates a unique mechanism for studying quantum phenomena related to spin-lattice couplings.
Article
Materials Science, Multidisciplinary
H. Yamaguchi, S. C. Furuya, S. Morota, S. Shimono, T. Kawakami, Y. Kusanose, Y. Shimura, K. Nakano, Y. Hosokoshi
Summary: We present a model compound for a mixed-spin ferromagnetic chain, designed based on organic radicals. The compound shows ferromagnetic behavior and exhibits a double-peak structure in its magnetic specific heat, indicating a phase transition. Quantum Monte Carlo calculations and modified spin-wave theory explain the observed characteristics.
Article
Materials Science, Multidisciplinary
G. Gitgeatpong, Y. Zhao, J. A. Fernandez-Baca, T. Hong, T. J. Sato, P. Piyawongwatthana, K. Nawa, P. Saeaun, K. Matan
Summary: The magnetic properties of the antiferromagnet ZnxCu2-xV2O7 (ZnCVO) were thoroughly investigated. The study found similarities between ZnCVO and β-Cu2V2O7 (β-CVO) in terms of crystal structure and macroscopic magnetic properties. The spin network of ZnCVO was found to be better described by an anisotropic 2D spin network, different from the predicted 2D honeycomb structure.
Article
Materials Science, Multidisciplinary
K. Matan, T. Ono, S. Ohira-Kawamura, K. Nakajima, Y. Nambu, T. J. Sato
Summary: The spin dynamics of the spin-1/2 kagome-lattice antiferromagnet Cs2Cu3SnF12 were investigated using high-resolution, time-of-flight inelastic neutron scattering. The results showed the presence of a flat mode and a low-energy dispersive mode, which can be described by the linear spin-wave theory. However, three weakly dispersive modes between 9 and 14 meV could not be explained by the theory and were suggested to be attributed to two-spinon bound states.
Article
Materials Science, Multidisciplinary
H. Yamaguchi, N. Uemoto, T. Okubo, Y. Kono, S. Kittaka, T. Sakakibara, T. Yajima, S. Shimono, Y. Iwasaki, Y. Hosokoshi
Summary: The model compound with a spin-1/2 frustrated square lattice exhibits unique magnetization curve and magnetic characteristics, indicating the presence of one-dimensional antiferromagnetic correlations. A gapless phase induced by the magnetic field transitioned to an ordered state with 2D characteristics. These results extend the spin-1 Haldane state to a 2D system, showing that the gapped ground state in the spin-1/2 frustrated square lattice is due to frustration-induced one-dimensionalization.
Article
Materials Science, Multidisciplinary
H. Yamaguchi, Y. Iwasaki, Y. Kono, T. Okubo, S. Miyamoto, Y. Hosokoshi, A. Matsuo, T. Sakakibara, T. Kida, M. Hagiwara
Summary: This study introduces a model compound with a spin-1/2 spatially anisotropic frustrated square lattice, showing an unconventional gradual increase in low-temperature magnetization curve and one-dimensional characteristics indicated by specific heat and electron spin resonance signals. These results demonstrate quantum critical behavior associated with one-dimensionalization caused by frustrated interactions in the spin-1/2 spatially anisotropic square lattice.
Article
Materials Science, Multidisciplinary
P. Saeaun, Y. Zhao, P. Piyawongwatthana, T. J. Sato, F. C. Chou, M. Avdeev, G. Gitgeatpong, K. Matan
Article
Materials Science, Multidisciplinary
H. Yamaguchi, Y. Iwasaki, Y. Kono, T. Okita, A. Matsuo, M. Akaki, M. Hagiwara, Y. Hosokoshi
Article
Materials Science, Multidisciplinary
Y. Iwasaki, T. Okabe, N. Uemoto, Y. Kono, Y. Hosokoshi, S. Nakamura, S. Kittaka, T. Sakakibara, M. Hagiwara, T. Kawakami, H. Yamaguchi
Article
Materials Science, Multidisciplinary
Y. Kono, T. Okabe, N. Uemoto, Y. Iwasaki, Y. Hosokoshi, S. Kittaka, T. Sakakibara, H. Yamaguchi
