Crystal Defect Doping on Antiferromagnetic Topological Insulator Candidate EuMg 2 Bi 2
Not provided.
Chemistry↗
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Paramagnetic Properties of Rare Earth Hydroxides, Oxalates, and Dibutyl Phosphates
Magnetic separations present a promising approach for the recovery of rare earth (RE) elements from mixtures, particularly when coupled with precipitation techniques that enhance process efficiency and selectivity. However, the magnetic properties of RE materials typically encountered in the separations industry are not well characterized. Here, we synthesized a series of RE materials, combining four REs – praseodymium (Pr), neodymium (Nd), terbium (Tb), and dysprosium (Dy) – with three precipitating agents – hydroxide, oxalate, and dibutyl phosphate. All materials showed typical paramagnetic behavior consistent with the Curie-Weiss law. At low temperatures, we observed weak antiferromagnetic correlations, which were more pronounced for the lighter RE ions (Pr, Nd). Particle morphology and crystallography analyses showed that the dibutyl phosphates were well-ordered metal-organic frameworks, the oxalates were crystals with mixed hydration states, and the hydroxides were mostly amorphous. Regardless of the degree of crystallinity, the effective magnetic moments aligned well with theoretical estimates based on Hund's rules and 4f electron configurations of the corresponding RE ions. For a given RE ion, the magnetophoretic response was thus determined by the size of the particles rather than specific metal-ligand coupling, with dibutyl phosphate promoting the formation of larger crystals that were the most strongly attracted to magnets.
Wang, Qingpu (ORCID:0000000156041571)↗
Spin-polarized imaging of the antiferromagnetic structure and field-tunable bound states in kagome magnet FeSn
Abstract Kagome metals are an exciting playground for the explorations of novel phenomena at the intersection of topology, electron correlations and magnetism. The family of FeSn-based kagome magnets in particular attracted a lot of attention for simplicity of the layered crystal structure and tunable topological electronic band structure. Despite a significant progress in understanding their bulk properties, surface electronic and magnetic structures are yet to be fully explored in many of these systems. In this work, we focus on a prototypical kagome metal FeSn. Using a combination of spin-averaged and spin-polarized scanning tunneling microscopy, we provide the first atomic-scale visualization of the layered antiferromagnetic structure at the surface of FeSn. In contrast to the field-tunable electronic structure of cousin material Fe 3 Sn 2 that is a ferromagnet, we find that electronic density-of-states of FeSn is robust to the application of external magnetic field. Interestingly, despite the field insensitive electronic band structure, FeSn exhibits bound states tied to specific impurities with large effective moments that strongly couple to the magnetic field. Our experiments provide microscopic insights necessary for theoretical modeling of FeSn and serve as a spring board for spin-polarized measurements of topological magnets in general.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Effect of Mn doping and charge transfer on LaTi 1- x Mn x O 3
Here, we report the magnetic and electronic transport properties of Mn-doped LaTi 1-x Mn x O 3 (x= 0, 0.1, 0.3, 0.5) as a function of temperature and an applied magnetic field. It was found that the Mn-doped samples show a magnetic transition which is not present in the parent LaTiO 3 . The Mn-doped samples showed fluctuations in magnetization at low fields below their Néel transition temperature indicating electronic phase separation in the material. Increased Mn content in the sample strengthens the ferromagnetic-like moment while maintaining G-type antiferromagnetic phase by charge transfer from Mn to Ti and influencing orbital ordering of the Ti 3+ t 2g orbitals. The results are discussed in parallel with transport and bulk magnetization measurements detailing the electronic behavior. An additional context for the mechanism is supported by first-principles density-function theory calculations.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Spin dynamics in NaFeAs and NaFe 0.53 Cu 0.47 As probed by resonant inelastic x-ray scattering
The parent compounds of iron-based superconductors are magnetically ordered bad metals, with superconductivity appearing near a putative magnetic quantum critical point. The presence of both Hubbard repulsion and Hund’s coupling leads to rich physics in these multiorbital systems, and motivated descriptions of magnetism in terms of itinerant electrons or localized spins. The NaFe 1–x Cu x As series consists of magnetically ordered bad metal (x = 0), superconducting (x ≈ 0.02) and magnetically ordered semiconducing/insulating (x ≈ 0.5) phases, providing a platform to investigate the connection between superconductivity, magnetism and electronic correlations. Here we use x-ray absorption spectroscopy and resonant inelastic x-ray scattering to study the valence state of Fe and spin dynamics in two NaFe 1–x Cu x As compounds (x = 0 and 0.47). We find that magnetism in both compounds arises from Fe 2+ atoms, and exhibits underdamped dispersive spin waves in their respective ordered states. The dispersion of spin excitations in NaFe 0.53 Cu 0.47 As is consistent with being quasi-one-dimensional. Compared to NaFeAs, the band top of spin waves in NaFe 0.53 Cu 0.47 As is slightly softened with significantly more spectral weight of the spin excitations. Here, our results indicate the spin dynamics in NaFe 0.53 Cu 0.47 As arise from localized magnetic moments and suggest the iron-based superconductors are proximate to a correlated insulating state with localized iron moments.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Spin-triplet superconductivity driven by finite-momentum spin fluctuations
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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Total Angular Momentum Dichroism of the Terahertz Vortex Beams at the Antiferromagnetic Resonances
Here, terahertz vortex beams with different superposition of the orbital angular momentum $\textit{l}$ = ± 1, ±2, ±3, and ±4 and spin angular momentum σ = ±1 were used to study antiferromagnetic (AFM) resonances in TbFe 3 (BO 3 ) 4 and Ni 3 TeO 6 single crystals. In both materials we observed a strong vortex beam dichroism for the AFM resonances that are split in external magnetic field. The magnitude of the vortex dichroism is comparable to that for conventional circular dichroism due to σ. The selection rules at the AFM resonances are governed by the total angular momentum of the vortex beam: $\textit{j}$ = σ + $\textit{l}$. In particular, for $\textit{l}$ = ±2, ±3, and ±4 the sign of $\textit{l}$ is shown to dominate over that for conventional circular polarization σ.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Intrinsic spin Nernst effect of magnons in a noncollinear antiferromagnet
Not Available
36 MATERIALS SCIENCE↗
Controlling magnetic exchange and anisotropy by nonmagnetic ligand substitution in layered 𝑀P𝑋 3 (𝑀 = Ni, Mn; 𝑋 = S, Se)
Recent discoveries in two-dimensional magnetism have intensified the investigation of van der Waals magnetic materials and further improved our ability to tune their magnetic properties. Tunable magnetism has been widely studied in antiferromagnetic metal thiophosphates 𝑀P𝑋 3 . Substitution of metal ions 𝑀 has been adopted as an important technique to engineer the magnetism in 𝑀P𝑋 3 . In this work, we have studied the previously unexplored chalcogen 𝑋 substitutions in 𝑀P𝑋 3 (𝑀 = Mn/Ni; 𝑋 = S/Se). We synthesized the single crystals of MnPS 3−𝑥 Se 𝑥 (0 ≤ 𝑥 ≤ 3) and NiPS 3−𝑥 Se 𝑥 (0 ≤ 𝑥 ≤ 1.3) and investigated the systematic evolution of the magnetism with varying 𝑥. Our study reveals the effective tuning of magnetic interactions and anisotropies in both MnPS 3 and NiPS 3 upon Se substitution. Such efficient engineering of the magnetism provides a suitable platform to understand the low-dimensional magnetism and develop future magnetic devices.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
Highly Tunable Magnetic Phases in Transition-Metal Dichalcogenide Fe 1 / 3 + δ NbS 2
Not Available
2-dimensional systems↗
Programmable Phase Selection between Altermagnetic and Noncentrosymmetric Polymorphs of MnTe on InP via Molecular Beam Epitaxy
This dataset contains DFT input and output files supporting the theoretical modeling in the associated publication (ACS Appl. Mater. Interfaces 2026, 18, 15654-15664). The calculations model the interfacial energetics of two MnTe polymorphs — NiAs-MnTe (hexagonal, alpha phase) and ZnS-MnTe (cubic, gamma phase) — on InP(111) substrates with two surface terminations: In-terminated InP(111)A and P-terminated InP(111)B. This gives four interface configurations: NiAs on In-terminated (experimentally observed), NiAs on P-terminated (computed for comparison), ZnS on In-terminated (computed for comparison), and ZnS on P-terminated (experimentally observed). The dataset is organized into four calculation types, each covering all four polymorph/termination combinations: (i) Slabs: Pristine MnTe/InP heterostructure slabs used to compute total energies and interface energy densities (Eint) for all four configurations, as reported in Fig. 6 of the main text. (ii) Disorder: Same slab geometries with a P_Te + Te_P antisite defect pair introduced near the interface, used to assess chemical intermixing effects on interface stability (Fig. S8, SI). (iii) Strain: Pristine slab calculations with in-plane lattice parameters strained by -1% and +1% relative to the InP lattice constant, used to evaluate strain-dependent interface energetics (Fig. S9, SI). (iv) Charge_Density: Single-point calculations on the full heterostructure, the isolated InP slab, and the isolated MnTe slab at fixed geometry, used to compute differential charge density plots showing interfacial charge accumulation and depletion as a function of surface termination (Fig. S10, SI). Each calculation folder contains INCAR, KPOINTS, POSCAR, CONTCAR, OUTCAR, and POTCAR_info.txt (PAW potential information, excluding the full POTCAR due to VASP licensing restrictions). The calculations were performed using VASP 6.4.3 with PBE exchange-correlation, PAW potentials, a Hubbard correction of Ueff = 5 eV on Mn d-states, and A-type AFM spin initialization.
36 MATERIALS SCIENCE↗
Spin disorder in a stacking polytype of a layered magnet
Strongly correlated ground states and exotic quasiparticle excitations in low-dimensional systems are central research topics in the solid-state research community. The present work develops a layered material and explores the physical properties. Single crystals of 3R–Na 2 MnTeO 6 were synthesized via a flux method. Single-crystal x-ray diffraction and transmission electron microscopy reveal a crystal structure with ABC-type stacking and an R–3 space group, which establishes this material as a stacking polytype to previously reported 2H–Na 2 MnTeO 6 . Magnetic- and heat-capacity measurements demonstrate dominant antiferromagnetic interactions, the absence of long-range magnetic order down to 0.5 K, and field-dependent short-range magnetic correlations. A structural transition at ~23 K observed in dielectric measurements may be related to displacements of the Na positions. In conclusion, our results demonstrate that 3R–Na 2 MnTeO 6 displays low-dimensional magnetism, disordered structure and spins, and the system displays a rich structure variety.
36 MATERIALS SCIENCE↗
Review of honeycomb-based Kitaev materials with zigzag magnetic ordering
The search for a Kitaev quantum spin liquid in crystalline magnetic materials has fueled intense interest in the two-dimensional honeycomb systems. Many promising candidate Kitaev systems are characterized by a long-range-ordered magnetic structure with an antiferromagnetic zigzag-type order, where the static moments form alternating ferromagnetic chains. Recent experiments on high-quality single crystals uncovered the existence of intriguing multi-k magnetic structures, which evolved from zigzag structures. Those discoveries have sparked new theoretical developments and amplified interest in these materials. We present an overview of the honeycomb materials known to display this type of magnetic structure and provide detailed crystallographic information for the possible single- and multi-k variants.
36 MATERIALS SCIENCE↗
Spin-orbital liquids and insulator-metal transitions on the pyrochlore lattice
The two orbital Hubbard model, with the electrons additionally coupled to a complex magnetic background, arises in the pyrochlore molybdates. The background involves local moments Hund's coupled to the electrons, driving double exchange ferromagnetism, and antiferromagnetic (AF) tendency arising from competing superexchange. The key scales include the Hubbard repulsion and the superexchange, both of which can be tuned in these materials. They control the phase transition from a ferromagnetic metal to a spin glass metal and then to a spin glass (Mott) insulator. We provide a comprehensive description of the ground state of this model using an unrestricted Hartree-Fock scheme implemented via a simulated annealing procedure and establish the metal-insulator transition line for varying Hubbard interaction and superexchange. The electrons see an effective disorder, due to orbital frustration, already in the ferromagnetic phase. The disorder is further enhanced by antiferromagnetic coupling and the resulting magnetic disorder. As a result, increasing AF coupling shifts the metal-insulator transition to lower Hubbard interaction and gives it an additional "Anderson" character. In conclusion, we provide detailed results on the magnetic and orbital correlations, the density of states, and the optical conductivity.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Magnetic behavior of manganese chloride on Kagome and honeycomb lattices
The magnetic properties of transparent pink Na 2 Mn 3 Cl 8 and NaMnCl3 are presented. For both phases, the effective magnetic moments are large, while the Curie-Weiss thetas are below 10 K. The compounds crystallize in the trigonal R-3m and R-3 space groups, respectively. A Kagome plane of Mn 2+ octahedrally coordinated to Cl- is found in Na 2 Mn 3 Cl 8 and the material has no apparent magnetic ordering above 1.8 K, while the octahedrally coordinated, honeycomb network of Mn 2+ in NaMnCl 3 orders antiferromagnetically at 6.3 ± 0.2 K. The heat capacity of NaMnCl3 has one transition, consistent with the susceptibility, while Na 2 Mn 3 Cl 8 exhibits a more complex heat capacity with two peaks, at 0.6 K and 1.4 K. A third, broad peak near 6.2 K in the heat capacity of Na 2 Mn 3 Cl 8 is problematic but may be due to the intergrowth of NaMnCl 3 domains.
36 MATERIALS SCIENCE↗
Structure and properties of NdCuGa 3 single crystals
Here this manuscript reports on the structural and magnetic properties of NdCuGa 3 using powder and single crystal X-ray diffraction (XRD), zero-field single crystal neutron diffraction, magnetization, and specific heat measurements. Our XRD on a single crystal specimen of NdCuGa3 confirmed that it crystallizes in the tetragonal BaNiSi 3 -type structure. A magnetic phase transition at T N = 3.3 K is assessed using specific heat and ac magnetic susceptibility measurements. No additional anomaly below T N down to 50 mK was detected by performing specific heat measurements. Neutron single crystal diffraction data collected at T = 300 mK confirm the antiferromagnetic phase below T N = 3.3 K with the propagation vector $\vec{\tau}$ = (0.2, 0, 0). Possible magnetic structure solutions of NdCuGa 3 are discussed
36 MATERIALS SCIENCE↗
Interplay between defect transport and cation spin frustration in corundum-structured oxides
Despite the fundamental importance of mass transport, there is still a lack of knowledge regarding the mechanisms in many materials. In particular, how the magnetic spin structure interacts with migrating defects is unclear. In this work, using density functional theory to examine cation interstitial transport in antiferromagnetic corundum-structured oxides, we reveal an interplay between the migration of the interstitial and the magnetic structure of the oxide. The magnetic spin configuration impacts the migration energy of the migrating defect but, critically, the defect modifies the spin configuration. Thus, the two aspects change in concert to modify one another. This has profound implications for mass transport in magnetic materials.
36 MATERIALS SCIENCE↗