Article
Chemistry, Multidisciplinary
Wenxiao Shi, Jie Zheng, Zhe Li, Mengqin Wang, Zhaozhao Zhu, Jine Zhang, Hui Zhang, Yunzhong Chen, Fengxia Hu, Baogen Shen, Yuansha Chen, Jirong Sun
Summary: Artificial oxide heterostructures provide promising platforms for exploring emergent quantum phases, including the interesting phenomenon of interfacial magnetism between non-magnetic compounds. This study reports the emergence of a robust ferromagnetic phase at the (111)-oriented heterointerface between paramagnetic CaRuO3 and diamagnetic SrTiO3. The phase exhibits a high Curie temperature, large saturation magnetization, and tunable magnetic anisotropy.
Article
Physics, Multidisciplinary
Mohammed Moaied, S. Soliman
Summary: Using first-principles calculations, a novel family of 2D magnetic materials, hydrogenated chromium tri-chalcogenides, was predicted and synthesized in this study. These materials exhibit semiconductor band structures, with antiferromagnetic order in Cr-O-3-H-3 and strong in-plane magnetic anisotropy in the rest. Curie temperature and weakly frequency-dependent dielectric functions were obtained through simulations.
Article
Materials Science, Multidisciplinary
Xiaotian Fang, Baozeng Zhou, Xiaocha Wang, Wenbo Mi
Summary: In this study, the electronic structure and magnetic properties of a two-dimensional (2D) OsI3 monolayer were investigated using first-principles calculations. The results show that the monolayer exhibits various orbital orderings and magnetic states, and can be modulated by strain to control magnetic anisotropy and Curie temperature, indicating its potential application in spintronics.
MATERIALS TODAY PHYSICS
(2022)
Article
Multidisciplinary Sciences
Hang Chi, Yunbo Ou, Tim B. Eldred, Wenpei Gao, Sohee Kwon, Joseph Murray, Michael Dreyer, Robert E. Butera, Alexandre C. Foucher, Haile Ambaye, Jong Keum, Alice T. Greenberg, Yuhang Liu, Mahesh R. Neupane, George J. de Coster, Owen A. Vail, Patrick J. Taylor, Patrick A. Folkes, Charles Rong, Gen Yin, Roger K. Lake, Frances M. Ross, Valeria Lauter, Don Heiman, Jagadeesh S. Moodera
Summary: In this study, a strain tunable Berry curvature induced reversal of the anomalous Hall effect in Cr2Te3 is demonstrated. The magnetic and topological properties of Cr2Te3 thin films are investigated, showing the presence of strain-modulated magnetic layers/domains and offering new opportunities for topological electronics.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Jingjuan Su, Yihang Bai, Puyuan Shi, Yufei Tu, Bing Wang
Summary: Recent experiments have shown that two-dimensional (2D) magnetism has attracted strong interest in advanced spintronics applications. However, the limited Curie temperature and magnetic anisotropy energy (MAE) hinder their potential applications. Through density functional theory calculations, we have predicted a stable 2D monolayer of Na3VAs2, which exhibits intrinsic ferromagnetic (FM) order and a high MAE (570 μeV per V atom). Monte Carlo simulation reveals that this monolayer has a Curie temperature (TC) of up to 305 K based on anisotropic Heisenberg mode. In addition, the 2D Na3VAs2 monolayer exhibits ideal half-metallic properties, which are maintained under various strains, and possesses good dynamic, thermal, and mechanical stability. The exceptional properties of the Na3VAs2 monolayer make it a promising candidate for spintronic devices.
RESULTS IN PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Dian Huang, Xianbin Zhang, Yidong Yang, Wei Guo, Xujin Dang
Summary: In this study, the electronic structures and magnetic properties of alloy compounds Cr8_xTMxBr24 (TM = Mo/W, x = 1-4) were investigated by replacing Cr atoms in monolayer CrBr3. The alloy compounds maintain their original semiconductor properties, with some becoming direct bandgap semiconductors. The ferromagnetic coupling and magnetic anisotropic energy values of the compounds are significantly enhanced. The alloy compounds also show an increase in Curie temperature, providing a theoretical basis for the development of spintronic devices based on CrBr3.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Nanoscience & Nanotechnology
Imran Khan, Javed Ahmad, Muhammad Ehsan Mazhar, Jisang Hong
Summary: By utilizing the magnetic proximity effect and biaxial strain, the magnetic ground state, band gap enhancement, and valley polarization in WSe2/CrSnSe3 heterostructures can be controlled. Different magnetic anisotropy and Curie temperatures were observed in pristine and strained structures. Strain also enhanced valley splittings, providing a potential method to tune the valley splitting in the heterostructures.
Article
Chemistry, Physical
Shiming Yan, Yue Hu, Deyou Jin, Ru Bai, Wen Qiao, Tiejun Zhou
Summary: In this study, the electric field dependence of magnetic anisotropy in MgO-based heterojunction consisting of a new Heusler alloy, Rh2CoSb, is investigated using first-principles calculations. The results show that the Rh-terminated MgO/Rh2CoSb heterojunction exhibits perpendicular magnetic anisotropy and a giant VCMA effect.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Chen Li, Ke Liu, Dequan Jiang, Cheng Jin, Tianyao Pei, Ting Wen, Binbin Yue, Yonggang Wang
Summary: This study reports materials with negative, zero, and positive thermal expansion behaviors, which are hexagonal CrTe, monoclinic Cr3Te4, and trigonal Cr5Te8 in NiAs-type defective Cr1-delta Te. These materials show obvious anisotropic thermal expansion and the properties are confirmed to be originated from the magnetovolume effect through magnetic measurements. The materials with similar compositions but different structures provide a new research direction for tuning the negative thermal expansion properties of materials and searching for materials with zero thermal expansion.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
S. Udhayakumar, G. Jagadish Kumar, E. Senthil Kumar, M. Navaneethan, K. Kamala Bharathi
Summary: The study investigated the magnetic anomalies of Sr-doped LiFe5O8 materials, showing that Sr doping leads to low-temperature magnetic anomalies and exhibits hard magnetic behavior.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Multidisciplinary
Guibo Zheng, Shuixian Qu, Wenzhe Zhou, Fangping Ouyang
Summary: In this study, a new Janus TaNF monolayer with excellent piezoelectric properties and intrinsic valley splitting is predicted. This is due to the spontaneous spin polarization, the spatial inversion symmetry breaking, and strong spin-orbit coupling. TaNF also shows potential as a 2D magnetic material with high Curie temperature and large magnetic anisotropy energy. Biaxial strain can effectively control the band gap and tune the magnitude of valley splitting. Curie temperature reaches 373 K under -3% biaxial strain, indicating potential high-temperature applications for spintronic and valleytronic devices.
FRONTIERS OF PHYSICS
(2023)
Article
Physics, Applied
Xiaokun Huang, Jinlin Xu, Xin Nie, Chao Chen, Wei Wang, Guang Song, Xiangping Jiang, Jun-Ming Liu
Summary: This study focuses on the bilayer structure of 2D van der Waals ferromagnetic materials and predicts through first-principles calculations that beryllium ion intercalation can significantly enhance interlayer ferromagnetic coupling. The enhancement is achieved by reducing the interlayer distance and orbital hybridization between beryllium ions and interfacial sites. Beryllium ion intercalation also contributes to electron doping, favoring the enhanced intralayer ferromagnetic coupling.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Chao Xin, Zhen Fan, Zhixin Sun, Hui Li, Guangyong Jin, Feng Pan, Yu Sui
Summary: This work analyzes a novel class of 2D monolayer materials with predicted spin-polarized semi-conductivity, partially compensated antiferromagnetic (AFM) order, fairly high Curie temperature, and out-of-plane polarization for the first time. By using density functional theory calculations and ab initio molecular dynamics (AIMD), the thermal and dynamic stabilities of six functionalized Mo2CXX' were studied. Results show that Mo2C-FO could be a novel monolayer electromagnetic material where the magnetization can be modulated by electric polarization.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Applied
Bin Li, Runnan Zhang, Liang Zhou, Linjing Wang, Zijun Yan, Hongtao He, Gan Wang
Summary: A delicate superlattice structure of Cr2Te3/Bi-2/Bi2Te3 has been constructed based on the chemical reduction at the interface. The growth was conducted by molecular beam epitaxy, and the structural characterizations have provided solid evidence of the designed structure. The interfaces between Cr2Te3, Bi-2, and Bi2Te3 are sharp, and ferromagnetism has been introduced in this system as revealed by the negative magnetoresistance curve and the anomalous Hall effect.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Condensed Matter
Zhuojun Zhao, Zhenning Sun, Xinru Li, Yunjin Yu
Summary: In recent years, MA2Z4 (M = transition metal; A = Si or Ge; Z = N, P or As) has attracted much attention as a new family of two-dimensional (2D) transition metal compounds. Our study shows that monolayer VGe2P4 and its Janus structures VGe2P3N and VGeSnP4 are ferromagnets with dynamical, energetic, and mechanical stability. Janus modification can also enhance the Curie temperature and the magnetic anisotropy energy of the compounds.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Qian Yang, Yu Zhang, Zhong-Qiu Fu, Yulong Chen, Zengfeng Di, Lin He
Summary: This research successfully demonstrates a technique to create patterned graphene quantum dots with nanoscale precision in their locations using a voltage pulse from a scanning tunneling microscopy tip. By accurately tuning the coordinates of the STM tip, the designed patterns of the GQDs are successfully generated. Spatial-resolved measurements show that the patterns of the GQDs strongly affect the local electronic properties and two-dimensional distributions of local density of states in graphene.
Article
Physics, Multidisciplinary
Nicolas Morales-Duran, Nai Chao Hu, Pawel Potasz, Allan H. MacDonald
Summary: Moiré materials in two-dimensional semiconductor heterobilayers are quantum simulators that can simulate unconventional states of matter in Hubbard physics, such as spin liquids, insulating ferromagnets, and superconductors. The interaction between electrons or holes in Moiré materials is more relevant compared to atomic scale systems.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Qi Zheng, Yu-Chen Zhuang, Qing-Feng Sun, Lin He
Summary: This study demonstrates that the electron whispering-gallery modes and atomic collapse states can coexist in graphene/WSe2 heterostructure quantum dots.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Applied
Yi-Wen Liu, Chen-Yue Hao, Lin He
Summary: Researchers have demonstrated the ability to controllably stabilize van der Waals materials with custom-designed twist angles, such as the magic angle, by tailoring the adhesive-energy landscape of graphene nanostructures. They found that the custom-built nanoscale magic-angle-twisted bilayer graphene retains its robust flat band properties, even at small sizes comparable to a single moiré spot. The researchers also showed that the graphene nanostructure can be manipulated at the atomic scale through the use of a one-dimensional tilt grain boundary.
PHYSICAL REVIEW APPLIED
(2022)
Review
Nanoscience & Nanotechnology
Emma C. Regan, Danqing Wang, Eunice Y. Paik, Yongxin Zeng, Long Zhang, Jihang Zhu, Allan H. MacDonald, Hui Deng, Feng Wang
Summary: This Review discusses two approaches for realizing emergent excitonic physics in two-dimensional semiconductor heterostructures: the introduction of a moire superlattice and the formation of an optical cavity.
NATURE REVIEWS MATERIALS
(2022)
Review
Nanoscience & Nanotechnology
Libor Smejkal, Allan H. MacDonald, Jairo Sinova, Satoru Nakatsuji, Tomas Jungwirth
Summary: This review organizes the current understanding of anomalous antiferromagnetic materials that generate a Hall effect and discusses their applications in spintronics, topological condensed matter, and multipole magnetism.
NATURE REVIEWS MATERIALS
(2022)
Article
Physics, Multidisciplinary
Yi-Wen Liu, Zhen Zhan, Zewen Wu, Chao Yan, Shengjun Yuan, Lin He
Summary: Exotic electronic states can be achieved through the coupling of zeroth PLLs in strained graphene, providing a new approach to engineering the electronic properties of graphene.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Ya-Ning Ren, Qiang Cheng, Qing-Feng Sun, Lin He
Summary: In this study, the valley-polarized energy spectra of graphene quantum dots were achieved by continuously tunable Berry phases through adjusting the magnetic field. The large and continuously tunable valley-polarized energy spectra were realized by altering the Berry phase to noninteger multiples of zero. This research sheds light on graphene-based valleytronics and provides new experimental and theoretical evidence.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Ya-Ning Ren, Zhen Zhan, Yi-Wen Liu, Chao Yan, Shengjun Yuan, Lin He
Summary: In two-dimensional small-angle twisted bilayers, the atomic-scale reconstruction caused by van der Waals interlayer interaction can be mapped by introducing a topmost small-period graphene moire pattern. This pattern magnifies sub-Angstrom lattice distortions in the small-angle twisted bilayer graphene by about 2 orders of magnitude, enabling real-space mapping of the networks of subdegree lattice rotations. This method provides a facile way to study subdegree lattice rotation in van der Waals systems.
Letter
Chemistry, Multidisciplinary
Mo-Han Zhang, Ya-Ning Ren, Qi Zheng, Xiao-Feng Zhou, Lin He
Summary: Two-dimensional h-BN and TMDs are commonly used as substrates for graphene due to their insulating and atomically flat properties. However, this study reveals unexpected sensitivity of graphene's electronic properties to these insulating substrates, even when the moire pattern generated between them is small. The electronic density in graphene exhibits a robust and long-ranged superperiodicity in graphene/TMD heterostructures, which arises from electron scattering between the two valleys of graphene. Scanning tunneling microscope and spectroscopy techniques reveal three distinct atomic-scale patterns of electronic density in every graphene/TMD heterostructure.
Article
Physics, Multidisciplinary
Qi Zheng, Yu-Chen Zhuang, Ya-Ning Ren, Chao Yan, Qing-Feng Sun, Lin He
Summary: In this study, quasibound states in elliptical and circular graphene quantum dots were systematically investigated through experiments and theoretical calculations. It was found that bonding and antibonding molecular collapse states formed by two coupled atomic collapse states, and the antibonding state can change into a Klein-tunneling-induced quasibound state, revealing a deep connection between atomic collapse states and the Klein tunneling.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Chao Yan, Ya-Xin Zhao, Yi-Wen Liu, Lin He
Summary: This study investigates the dynamics of nanobubbles in tiny-angle twisted bilayer graphene (TBG) and reveals the significant influence of the moire superlattice on the motion of nanoscale interfacial substances.
Article
Materials Science, Multidisciplinary
Yongxin Zeng, Allan H. MacDonald
Summary: This paper examines the influence of moiré patterns in semiconductor heterobilayers on exciton and trion states, comparing the differences to the case of excitons and trions in semiconductor quantum dots in the limit of strong moiré modulation potentials. The strategies for using optical properties as quantitative probes of moiré materials and the prospects of utilizing moiré materials to design unique light emitters are discussed.
Article
Materials Science, Multidisciplinary
B. Flebus, A. H. MacDonald
Summary: It has been found in recent experiments that phonons can be deflected by a magnetic field when flowing in response to a thermal gradient, leading to a thermal Hall effect. The ratio of phonon Hall conductivity ??H to the phonon longitudinal conductivity ??L in oxide dielectrics can exceed 10^-3 when phonon mean-free paths are longer than phonon wavelengths. Additionally, the ??H/??L ratio does not strongly depend on temperature. These observations suggest a mechanism related to phonon scattering from defects that break time-reversal symmetry, where Lorentz forces acting on charged defects result in significant skew-scattering amplitudes and related thermal Hall effects.
Article
Materials Science, Multidisciplinary
Yongxin Zeng, Fei Xue, Allan H. MacDonald
Summary: This study investigates the influence of an in-plane magnetic field and Coulomb interactions on the physics of quantum spin Hall insulators. By calculating phase diagrams and discussing possible experimental implications, the study demonstrates the system's instability against the formation of density-wave states when the band hybridization is weak and shows the appearance of distinct density-wave states as the strength of the in-plane magnetic field increases.
Article
Physics, Condensed Matter
Shivani Gohri, Jaya Madan, Rahul Pandey
Summary: This study improves the efficiency of SnS-based solar cells by implementing the glancing angle deposition approach and introducing a CZTSSe layer. The findings offer valuable insights for enhancing the design of SnS-based solar cells and making them more efficient.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Mahboubeh Yeganeh, Davoud Vahedi Fakhrabad
Summary: The lattice thermal conductivity of CdO monolayer was investigated, and it was found to be lower than that of bulk CdO due to the lower phonon lifetime and phonon group velocity. As a result, the monolayer exhibits higher thermoelectric efficiency compared to the bulk counterpart.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Shivam Srivastava, Prachi Singh, Anjani K. Pandey, Chandra K. Dixit
Summary: In this research paper, a novel equation of state (EOS) based on finite strain theories is proposed for predicting the thermo elastic properties of various materials. Extensive analysis and comparison with existing models and experimental data demonstrate the validity and effectiveness of the proposed EOS in capturing the unique thermodynamic behavior of nanomaterials, bulk metallic glasses, and superconductors. This research is of great importance in the fields of materials science, nanotechnology, and condensed matter physics.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Subrata Das, Sanjoy Kr Mahatha, Konstantin Glazyrin, R. Ganesan, Suja Elizabeth, Tirthankar Chakraborty
Summary: In this study, we investigated the structural evolution of Tb2Ti2O7 under external pressure and temperature, and confirmed the occurrence of an isostructural phase transition beyond 10 GPa pressure. This transition leads to changes in lattice parameters and mechanical properties, which can be understood in terms of localized rearrangement of atoms.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Hamze Mousavi
Summary: It has been found that undoped graphene sheet has zero states at the Fermi energy level, making it difficult for Cooper pairing to occur in the superconductive state. However, T-graphene, with physical properties similar to graphene, exhibits metallic behavior and has available electron states near the Fermi level. The gap equation for the s-wave superconductive state is derived based on the attractive Hubbard model and the Bogoliubov de Gennes equation for this two-dimensional metallic system. It is found that a nonzero critical temperature, τ, exists for different levels of electron-electron interaction, ǫ. τ has higher values when the system has electronic half band-filling, but decreases when the system does not have half band-filling. However, τ vanishes when ǫ becomes small enough near the band edges.
SOLID STATE COMMUNICATIONS
(2024)
