Article
Materials Science, Multidisciplinary
Chengxi Zhao, Kisung Kang, Joerg C. Neuefeind, Andre Schleife, Daniel P. Shoemaker
Summary: The ordered tetragonal intermetallic compound Cr2Al has been shown to form the same structure type as Mn2Au, which has potential in antiferromagnetic spintronics. The orientation-dependent magnetic properties of Cr2Al suggest similar behavior to Mn2Au, providing a second material candidate in the MoSi2 structure type.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Maksim E. Stebliy, Alexander G. Kolesnikov, Michail A. Bazrov, Michail E. Letushev, Alexey Ognev, Aleksandr Davydenko, Ekaterina Stebliy, Aleksei G. Kozlov, Xiao Wang, Caihua Wan, Chi Fang, Mingkun Zhao, Xiufeng Han, Alexander S. Samardak
Summary: The experimental study investigates the effect of electric current on the exchange bias field in the Pt/Co/NiO structure, attributing the changes mainly to heating effects and the low Neel temperature. The injection of spin current and Joule heating contribute to the repeated variations in H-EB field value.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Review
Chemistry, Physical
Yue Zhang, Taojian Fan, Sijie Yang, Fakun Wang, Sanjun Yang, Shuzhe Wang, Jianwei Su, Mei Zhao, Xiaozong Hu, Han Zhang, Tianyou Zhai
Summary: 2D layered phosphorous compounds (2D LPCs) have attracted extensive research interest due to their diverse physical and chemical properties, making them promising for applications in electronics, spintronics, optoelectronics, catalysts, and energy storage.
Article
Chemistry, Multidisciplinary
Takahide Kubota, Yusuke Shimada, Tomoki Tsuchiya, Tomoki Yoshikawa, Keita Ito, Yukiharu Takeda, Yuji Saitoh, Toyohiko J. Konno, Akio Kimura, Koki Takanashi
Summary: Heusler alloys exhibit various magnetic properties, including antiferromagnetism, with a typical application being exchange bias in layered structures. This study focused on a layered sample of Mn2VAl and Fe, showing exchange bias. Microscopic analysis revealed the importance of antiferromagnetic coupling and locally ordered phases in the generation of exchange bias.
Article
Chemistry, Multidisciplinary
Hyun-Joo Koo, Reinhard K. Kremer, Myung-Hwan Whangbo
Summary: We investigated the interactions that control the sign and strength of interlayer coupling in van der Waals ferromagnets and found that high-spin orbital interactions are crucial for understanding their ferromagnetism. The results explain several puzzling observations in these materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Hyun-Joong Kim, Seongsoo Yoon, Jae-Hyun Ha, Won-Chang Choi, Jung-Il Hong
Summary: The absence of net magnetization in antiferromagnets makes their magnetic anisotropy strong and robust against external magnetic fields, requiring a heating and cooling process to realign the spin structure. However, mechanical vibrations with relatively low frequencies can substitute the heating step and enable local control of the exchange bias effect in antiferromagnets. This technique allows for repeated post-readjustment of exchange bias effect in various directions, promoting wider integrations of exchange-biased systems in novel magnetic devices.
Article
Physics, Condensed Matter
Nirmal Roy, Md Arif Ali, Arpita Sen, D. T. Adroja, Prasenjit Sen, S. S. Banerjee
Summary: By exploring 40 nm diameter Co2C nanoparticles, a unique connection between EBE and MA at low temperatures is revealed, demonstrating distinctive properties. The exchange coupling of frozen ferromagnetic spins with a freely rotatable spin component results in the coexistence of ferromagnetism and a glassy behavior at low temperatures.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Inorganic & Nuclear
Qiong Yuan, Yin-Shan Meng, Yi-Quan Zhang, Chen Gao, Shan-Shan Liu, Bing-Wu Wang, Song Gao
Summary: The synthesis of fluoride-bridged dysprosium complexes and their magnetic properties are reported in this study. The nucleation of the complexes is influenced by the reaction solvents and the molar ratio of dysprosium and fluoride precursors. The synthesized trinuclear complex shows a triangular arrangement, while the tetranuclear complex displays a butterfly shape geometry. Fluoride ions have a significant influence on the orientation of the easy axis of magnetization and the exchange interactions.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Engineering, Biomedical
Jiahao Zhang, Sarah Guerin, Haoran Wu, Bin Xue, Yi Cao, Syed A. M. Tofail, Yancheng Wang, Damien Thompson, Wei Wang, Kai Tao, Deqing Mei, Ehud Gazit
Summary: Supramolecular layered assembly is achieved by introducing different functional groups to the triazine skeleton using vectored non-covalent interactions, resulting in high stability and broad-spectrum fluorescence. Additionally, bio-inspired superhydrophobic pillar arrays can be constructed using aromatic interactions.
BIO-DESIGN AND MANUFACTURING
(2022)
Article
Instruments & Instrumentation
M. Slezak, H. Nayyef, P. Drozdz, W. Janus, E. Swierkosz, M. Szpytma, M. Zajac, A. Koziol-Rachwal, T. Slezak
Summary: We investigated the magnetic properties of epitaxial CoO(111)/Fe(110) and NiO(111)/Fe(110) bilayers by combining X-ray magnetic linear and circular dichroism with magnetooptic Kerr effect measurements. Our results show that in both cases, the ferromagnetic sublayer plays a dominant role and determines the magnetic state of the neighboring antiferromagnet, although different interaction scenarios are observed. In CoO/Fe bilayers, the antiferromagnetic spins are frozen and their orientation is imprinted by the magnetization of the Fe layer. On the other hand, in NiO/Fe bilayers, the antiferromagnetic spins are rotatable and always follow the reorientation of the Fe magnetization.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
(2023)
Article
Physics, Applied
Jiafeng Feng, H. X. Wei, Yong Ren, Xinxi Li, X. F. Han
Summary: This study investigates the magnetoresistance (MR) effect and magnetic properties in (Co/Pt)(4)/Co/IrMn (SFM) and (Co/Pt)(4)/Co/IrMn/(Co/Pt)(2)/Co (DFM) structures. The research finds that the thickness of the IrMn layer has different effects on the antiferromagnetic and MR properties for these two structures. The DFM structure exhibits suppressed antiferromagnetic property and enhanced MR.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Oleg E. Parfenov, Dmitry Averyanov, Ivan S. Sokolov, Alexander N. Taldenkov, Igor A. Karateev, Andrey M. Tokmachev, Vyacheslav G. Storchak
Summary: Coupling various functional properties in one material, particularly in a nanostructured material for practical applications, is an ongoing challenge. EuAl2Si2, a layered antiferromagnet with high carrier mobility, demonstrates outstanding structural quality, sharp interfaces, extreme magnetoresistance, and high carrier mobility above 10,000 cm(2) V-1 s(-1), making it a promising spintronic material seamlessly integrated with silicon technology for appealing applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Manish Kothakonda, Yanglin Zhu, Yingdong Guan, Jingyang He, Jamin Kidd, Ruiqi Zhang, Jinliang Ning, Venkatraman Gopalan, Weiwei Xie, Zhiqiang Mao, Jianwei Sun
Summary: Recent advances in 2D magnetism have led to increased interest in layered magnetic materials for spintronics applications. Layered semiconducting antiferromagnets exhibit unique low-dimensional semiconducting behavior and can be controlled by both charge and spin. However, synthesizing these compounds is challenging and rare. In this study, a high-throughput search based on first-principles was conducted to identify potentially stable mixed metal phosphorus trichalcogenides. Among the candidates, a stable semiconducting layered magnetic material, CdFeP2Se6, was successfully synthesized, exhibiting short-range antiferromagnetic order at 21 K with an indirect bandgap of 2.23 eV. This work suggests that high-throughput screening-assisted synthesis can be an effective method for discovering layered magnetic materials.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jiayong Lu, Junran Wu, Bin Huang, Yu Fang, Xiangmeng Deng, Jialin Zhang, Shanshan Chen, Seonghun Jeong, Jinbiao Liu, Changduk Yang
Summary: Ternary polymerization is a feasible method to optimize the properties of polymer matrix. By introducing the DDT unit as the third component, two terpolymer donors, L1 and L2, with deeper energy levels, enhanced molecular rigidity, and planarity are developed. The L1-based polymer solar cells blended with L8-BO exhibit well-defined nanofibrous morphology, face-on orientation, and record power conversion efficiency of up to 18.75%.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
S. Vivek, Ajith S. Kumar, C. S. Chitra Lekha, Swapna S. Nair
Summary: The exchange bias effects of BiFeO3 and lanthanum-doped BiFeO3 nanopowders were investigated, revealing a higher EB value for the doped sample possibly due to a combination of different models. Various magnetic experiments were conducted to study the thermoremanent and shell properties of the samples, indicating the presence of different shell structures.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Peitao Liu, Jiangang He, Bongjae Kim, Sergii Khmelevskyi, Alessandro Toschi, Georg Kresse, Cesare Franchini
PHYSICAL REVIEW MATERIALS
(2020)
Article
Physics, Multidisciplinary
Daniel Springer, Bongjae Kim, Peitao Liu, Sergii Khmelevskyi, Severino Adler, Massimo Capone, Giorgio Sangiovanni, Cesare Franchini, Alessandro Toschi
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Condensed Matter
Arsenii Gerasimov, Lars Nordstrom, Sergii Khmelevskyi, Vladimir V. Mazurenko, Yaroslav O. Kvashnin
Summary: This study investigates the magnetic moments of iron and cobalt in their B2-ordered alloy using a combination of density functional theory and dynamical mean-field theory. The results suggest that the Co magnetic moment strongly depends on the directions of surrounding magnetic moments, indicating a Stoner-type mechanism of magnetism. The study highlights the essential role of local correlations in stabilizing the local moment on Co in the absence of magnetic order at high temperatures.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Materials Science, Multidisciplinary
Radu Abrudan, Martin Hennecke, Florin Radu, Torsten Kachel, Karsten Holldack, Rolf Mitzner, Andreas Donges, Sergii Khmelevskyi, Andras Deak, Laszlo Szunyogh, Ulrich Nowak, Stefan Eisebitt, Ilie Radu
Summary: Experimental and theoretical evidence demonstrates the existence of element-specific magnetic damping parameters in the ultrafast magnetization response of a high-anisotropy ferrimagnetic DyCo5 alloy to femtosecond laser excitation. The significantly different demagnetization and remagnetization dynamics of Dy and Co magnetic moments are linked to their element-specific spin-orbit coupling strengths. These findings can be utilized for tuning the speed and magnitude of laser-driven magnetic processes in multicomponent magnetic materials.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Leonid Pourovskii, Sergii Khmelevskyi
Summary: This passage discusses the nature of order in low-temperature phases of certain materials and the hidden orders that may spark research interest. By studying neptunium dioxide NpO2, it is found that the ground-state order and magnetic excitations can be fully described by a low-energy Hamiltonian, revealing the multipolar exchange mechanism behind the anomalous volume contraction of the NpO2 HO phase.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Physics, Multidisciplinary
Yili Cao, Kun Lin, Sergii Khmelevskyi, Maxim Avdeev, Keith M. Taddei, Qiang Zhang, Qingzhen Huang, Qiang Li, Kenichi Kato, Chiu Chung Tang, Alexandra Gibbs, Chin-Wei Wang, Jinxia Deng, Jun Chen, Hongjie Zhang, Xianran Xing
Summary: By adjusting the Fe-Co content, researchers have optimized the thermal expansion behavior in a family of R-2(Fe, Co)(17) materials, achieving a record-wide SIV range with good cyclic stability. This breakthrough paves the way for exploiting thermal-expansion-control engineering and related functional materials.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Applied
M. Parzer, F. Garmroudi, A. Riss, S. Khmelevskyi, T. Mori, E. Bauer
Summary: This paper explores the aluminum-rich region in the Fe-V-Al material system and proposes a promising approach to improve the thermoelectric properties of p-type Heusler alloys. Experimental results show that Fe2VAlx alloys with high Al solubility exhibit significantly increased thermopower and reduced thermal conductivity. The analysis suggests that the enhancement is likely attributed to the formation of a resonant state at the valence band edge, which is supported by density-functional-theory calculations. This work paves the way for the development of p-type full-Heusler materials with enhanced thermoelectric performance.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Bence Bernath, Khrystyna Kutko, Steffen Wiedmann, Olga Young, Hans Engelkamp, Peter C. M. Christianen, Sergii Poperezhai, Leonid Pourovskii, Sergii Khmelevskyi, Dmytro Kamenskyi
Summary: The magnetostriction phenomenon is widely present in magnetically ordered materials and has broad application potential in high-tech fields such as precision machinery and robotics. This study reports a remarkable magnetostrictive response in the insulator paramagnet KEr(MoO4)(2), demonstrating that the anomaly is driven by a single-ion effect through a strong coupling between Er3+ ions and the crystal lattice. The microscopic mechanism behind the massive magnetostrictive response is revealed through a combination of low-temperature magnetization measurements, dilatometry, and ab initio calculations.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Multidisciplinary Sciences
Fabian Garmroudi, Michael Parzer, Alexander Riss, Andrei V. Ruban, Sergii Khmelevskyi, Michele Reticcioli, Matthias Knopf, Herwig Michor, Andrej Pustogow, Takao Mori, Ernst Bauer
Summary: Researchers have discovered a rare and unique molecular structure that can be manipulated by changing temperature and pressure, offering new possibilities for the manufacture of novel materials.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sergii Khmelevskyi, Peter Mohn
Summary: The magnetism of Co2FeSi alloy is studied using first-principles calculations. Fe and Co in Co2FeSi exhibit different magnetic behaviors, with Fe moments being localized and Co moments being itinerant. The inter-atomic exchange interactions between Fe and Co are strongly renormalized by magnetic disorder.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Fabian Garmroudi, Michael Parzer, Alexander Riss, Simon Beyer, Sergii Khmelevskyi, Takao Mori, Michele Reticcioli, Ernst Bauer
Summary: This study demonstrates a method to significantly increase the thermoelectric power of semimetallic Heusler alloys by transferring electronic states from within the pseudogap to higher energies. Experimental measurements on co-substituted systems show exceptionally large thermoelectric power factors.
MATERIALS TODAY PHYSICS
(2022)
Article
Multidisciplinary Sciences
Fabian Garmroudi, Michael Parzer, Alexander Riss, Cedric Bourges, Sergii Khmelevskyi, Takao Mori, Ernst Bauer, Andrej Pustogow
Summary: Unprecedented thermoelectric performance was discovered in NixAu1-x alloys, which challenges the common belief that good metals are not suitable for thermoelectric materials and provides a new approach for high thermoelectric performance.
Article
Materials Science, Multidisciplinary
S. Khmelevskyi, L. Pourovskii, E. A. Tereshina-Chitrova
Summary: The recently discovered UTe2 superconductor is a heavy-fermion mixed-valence system with peculiar properties. It shows no magnetic order but has strong anisotropy of magnetic susceptibility and superconducting critical field. By using dynamical mean-field theory calculations, it is found that the crystal-field splitting of the 5 f 2 ionic configuration derived from first principles agrees with experimental observations. The normal paramagnetic state of UTe2 is analogous to that of URu2Si2 in the Kondo arrest scenario.
Article
Materials Science, Multidisciplinary
Dario Fiore Mosca, Leonid Pourovskii, Beom Hyun Kim, Peitao Liu, Samuele Sanna, Federico Boscherini, Sergii Khmelevskyi, Cesare Franchini
Summary: In this work, the complex entanglement between spin interactions, electron correlation, and Janh-Teller structural instabilities in the 5d(1) J(eff) = 3/2 spin-orbit coupled double perovskite Ba2NaOsO6 is studied using first principles approaches. The origin of the observed quadrupolar canted antifferomagnetic is elucidated by combining noncollinear magnetic calculations with multipolar pseudospin Hamiltonian analysis and many-body techniques. It is found that the transition between different magnetic orders can be controlled by the strength of electronic correlation and the degree of Jahn-Teller distortions.
Article
Materials Science, Multidisciplinary
F. Garmroudi, A. Riss, M. Parzer, N. Reumann, H. Mueller, E. Bauer, S. Khmelevskyi, R. Podloucky, T. Mori, K. Tobita, Y. Katsura, K. Kimura
Summary: This study quantitatively analyzed the thermoelectric properties of Fe2V1-xTaxAl1-ySiy compounds, revealing an increase in band gap and Seebeck coefficient with Ta substitution, leading to an enhanced power factor with the highest value reported near room temperature. Additionally, the dominant scattering mechanisms of electrons were found to be fundamentally different between p-type and n-type materials.