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Chiral magnetic skyrmions1,2 are nanoscale vortex-like spin textures that form in the presence of an applied magnetic field in ferromagnets that support the Dzyaloshinskii–Moriya interaction (DMI) because of strong spin–orbit coupling and broken inversion symmetry of the crystal3,4. In sharp contrast to other systems5,6 that allow for the formation of a variety of two-dimensional (2D) skyrmions, in chiral magnets the presence of the DMI commonly prevents the stability and coexistence of topological excitations of different types7. Recently, a new type of localized particle-like object—the chiral bobber (ChB)—was predicted theoretically in such materials8. However, its existence has not yet been verified experimentally. Here, we report the direct observation of ChBs in thin films of B20-type FeGe by means of quantitative off-axis electron holography (EH). We identify the part of the temperature–magnetic field phase diagram in which ChBs exist and distinguish two mechanisms for their nucleation. Furthermore, we show that ChBs are able to coexist with skyrmions over a wide range of parameters, which suggests their possible practical applications in novel magnetic solid-state memory devices, in which a stream of binary data bits can be encoded by a sequence of skyrmions and bobbers.

The ability to controllably manipulate magnetic skyrmions, small magnetic whirls with particle-like properties, in nanostructured elements is a prerequisite for incorporating them into spintronic devices. Here, we use state-of-the-art electron holographic imaging to directly visualize the morphology and nucleation of magnetic skyrmions in a wedge-shaped FeGe nanostripe that has a width in the range of 45–150 nm. We find that geometrically-confined skyrmions are able to adopt a wide range of sizes and ellipticities in a nanostripe that are absent in both thin films and bulk materials and can be created from a helical magnetic state with a distorted edge twist in a simple and efficient manner. We perform a theoretical analysis based on a three-dimensional general model of isotropic chiral magnets to confirm our experimental results. The flexibility and ease of formation of geometrically confined magnetic skyrmions may help to optimize the design of skyrmion-based memory devices. Proposals for skyrmion-based high-density memory devices require an understanding of the formation and shape of skyrmions in confined geometries. Here, the authors use electron holography to image magnetic textures in FeGe nanostripes and explore the parameters governing skyrmion morphology.

Collecting the medical history during a first outpatient consultation plays an important role in making a diagnosis. However, it is a time-consuming process, and time is scarce in today's health care environment. The computer-assisted history taking (CAHT) systems allow patients to share their medical history electronically before their visit. Although multiple advantages of CAHT have been demonstrated, adoption in everyday medical practice remains low, which has been attributed to various barriers. This study aimed to implement a CAHT questionnaire for orthopedic patients in preparation for their first outpatient consultation and analyze its completion rate and added value. A multicenter implementation study was conducted in which all patients who were referred to the orthopedic department were invited to self-complete the CAHT questionnaire. The primary outcome of the study is the completion rate of the questionnaire. Secondary outcomes included patient and physician satisfaction. These were assessed via surveys and semistructured interviews. In total, 5321 patients were invited, and 4932 (92.7%) fully completed the CAHT questionnaire between April 2022 and July 2022. On average, participants (n=224) rated the easiness of completing the questionnaire at 8.0 (SD 1.9; 0-10 scale) and the satisfaction of the consult at 8.0 (SD 1.7; 0-10 scale). Satisfaction with the outpatient consultation was higher in cases where the given answers were used by the orthopedic surgeon during this consultation (median 8.3, IQR 8.0-9.1 vs median 8.0, IQR 7.0-8.5; P<.001). Physicians (n=15) scored the average added value as 7.8 (SD 1.7; 0-10 scale) and unanimously recognized increased efficiency, better patient engagement, and better medical record completeness. Implementing the patient's answers into the electronic health record was deemed necessary. In this study, we have shown that previously recognized barriers to implementing and adapting CAHT can now be effectively overcome. We demonstrated that almost all patients completed the CAHT questionnaire. This results in reported improvements in both the efficiency and personalization of outpatient consultations. Given the pressing need for personalized health care delivery in today's time-constrained medical environment, we recommend implementing CAHT systems in routine medical practice.

Some of the best-performing high-temperature magnets are Sm–Co-based alloys with a microstructure that comprises an Sm 2 Co 17 matrix and magnetically hard SmCo 5 cell walls. This generates a dense domain-wall-pinning network that endows the material with remarkable magnetic hardness. A precise understanding of the coupling between magnetism and microstructure is essential for enhancing the performance of Sm–Co magnets, but experiments and theory have not yet converged to a unified model. Here, transmission electron microscopy, atom probe tomography, and nanometer-resolution off-axis electron holography have been combined with micromagnetic simulations to reveal that the magnetization state in Sm–Co magnets results from curling instabilities and domain-wall pinning effects at the intersections of phases with different magnetic hardness. Additionally, this study has found that topologically non-trivial magnetic domains separated by a complex network of domain walls play a key role in the magnetic state by acting as nucleation sites for magnetization reversal. These findings reveal previously hidden aspects of magnetism in Sm–Co magnets and, by identifying weak points in the microstructure, provide guidelines for improving these high-performance magnetic materials.

Multilayers that comprise thin films of heavy metals and ferromagnets have been shown to host Néel-type magnetic skyrmions at room temperature. Fresnel defocus imaging in Lorentz transmission electron microscopy is a widely used technique for recording magnetic information about skyrmions. However, the visibility of Néel-type skyrmions in Fresnel defocus images is typically low, both because only a small component of their magnetic field contributes to the signal and because of the presence of diffraction contrast from the polycrystalline multilayer structure. Here, we take advantage of the out-of-plane hysteresis in such samples to record background-subtracted Fresnel defocus images. We demonstrate an improvement in magnetic signal-to-noise ratio and spatial resolution by a factor of 3 for a (Pt/Co/NiFe)×5 multilayer. We also use simulated Fresnel defocus images of Néel-type magnetic skyrmions to understand the influence of defocus on apparent skyrmion size.