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Spin waves in magnetic materials are promising information carriers for future computing technologies due to their ultra-low energy dissipation and long coherence length. Antiferromagnets are strong candidate materials due, in part, to their stability to external fields and larger group velocities. Multiferroic antiferromagnets, such as BiFeO3 (BFO), have an additional degree of freedom stemming from magnetoelectric coupling, allowing for control of the magnetic structure, and thus spin waves, with the electric field. Unfortunately, spin-wave propagation in BFO is not well understood due to the complexity of the magnetic structure. In this work, long-range spin transport is explored within an epitaxially engineered, electrically tunable, 1D magnonic crystal. A striking anisotropy is discovered in the spin transport parallel and perpendicular to the 1D crystal axis. Multiscale theory and simulation suggest that this preferential magnon conduction emerges from a combination of a population imbalance in its dispersion, as well as anisotropic structural scattering. This work provides a pathway to electrically reconfigurable magnonic crystals in antiferromagnets.

OBJECTIVES: Precision medicine is data-driven health care tailored to individual patients based on their unique attributes, including biologic profiles, disease expressions, local environments, and socioeconomic conditions. Emergency medicine (EM) has been peripheral to the precision medicine discourse, lacking both a unified definition of precision medicine and a clear research agenda. We convened a national consensus conference to build a shared mental model and develop a research agenda for precision EM. METHODS: We held a conference to (1) define precision EM, (2) develop an evidence-based research agenda, and (3) identify educational gaps for current and future EM clinicians. Nine preconference workgroups (biomedical ethics, data science, health professions education, health care delivery and access, informatics, omics, population health, sex and gender, and technology and digital tools), comprising 84 individuals, garnered expert opinion, reviewed relevant literature, engaged with patients, and developed key research questions. During the conference, each workgroup shared how they defined precision EM within their domain, presented relevant conceptual frameworks, and engaged a broad set of stakeholders to refine precision EM research questions using a multistage consensus-building process. RESULTS: A total of 217 individuals participated in this initiative, of whom 115 were conference-day attendees. Consensus-building activities yielded a definition of precision EM and key research questions that comprised a new 10-year precision EM research agenda. The consensus process revealed three themes: (1) preeminence of data, (2) interconnectedness of research questions across domains, and (3) promises and pitfalls of advances in health technology and data science/artificial intelligence. The Health Professions Education Workgroup identified educational gaps in precision EM and discussed a training roadmap for the specialty. CONCLUSIONS: A research agenda for precision EM, developed with extensive stakeholder input, recognizes the potential and challenges of precision EM. Comprehensive clinician training in this field is essential to advance EM in this domain.

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

BACKGROUND: It is essential that medical education (MedEd) fellows achieve desired outcomes prior to graduation. Despite the increase in postgraduate MedEd fellowships in emergency medicine (EM), there is no consistently applied competency framework. We sought to develop entrustable professional activities (EPAs) for EM MedEd fellows. METHODS: From 2021 to 2022, we used a modified Delphi method to achieve consensus for EPAs. EM education experts generated an initial list of 173 EPAs after literature review. In each Delphi round, panelists were asked to make a binary choice of whether to include the EPA. We determined an inclusion threshold of 70% agreement a priori. After the first round, given the large number of EPAs meeting inclusion threshold, panelists were instructed to vote whether each EPA should be included in the 20 most important EPAs for a MedEd fellowship. Modifications were made between rounds based on expert feedback. We calculated descriptive statistics. RESULTS: Seventeen experts completed four Delphi rounds each with 100% response. After Round 1, 87 EPAs were eliminated and two were combined. Following Round 2, 46 EPAs were eliminated, seven were combined, and three were included in the final list. After the third round, one EPA was eliminated and 13 were included. After the fourth round, 11 EPAs were eliminated. The final list consisted of 16 EPAs in domains of career development, education theory and methods, research and scholarship, and educational program administration. CONCLUSIONS: We developed a list of 16 EPAs for EM MedEd fellowships, the first step in implementing competency-based MedEd.

"Cuerpo-territorio" is a method stemming from Latin American geography, which recognizes the centrality of situated and embodied experiences as a form of knowing. We engaged with this method in the classroom to understand how students through their embodied and situated experiences had absorbed a post-development geographic course content and how these notions had remained with them. Given that emotions, particularly when elicited by images play a major role in consolidating knowledge, we asked students to explore their embodied feelings related to the course content by reflecting and representing them in a visual form on a poster. Through this paper, we aim to contribute to the debate on the importance of applying decolonial strategies in the classroom by widening the methodological toolbox of our geography colleagues. We find that, given the diversity of the students' population, working with a boundary object such as the posters helped students to relate to each other via the course content. Finally, reflecting and assimilating the course content through "cuerpo-territorio," we argue, was conducive to consolidating learning outcomes, while students experienced knowledge co-creation with their peers.

Interlayer coupling in materials, such as exchange interactions at the interface between an antiferromagnet and a ferromagnet, can produce exotic phenomena not present in the parent materials. While such interfacial coupling in magnetic systems is widely studied, there is considerably less work on analogous electric counterparts (i.e., akin to electric "exchange-bias-like" or "exchange-spring-like" interactions between two polar materials) despite the likelihood that such effects can also engender new features associated with anisotropic electric dipole alignment. Here, electric analogs of such exchange interactions are reported, and their physical origins are explained for bilayers of in-plane polarized Pb1-x Srx TiO3 ferroelectrics. Variation of the strontium content and thickness of the layers provides for deterministic control over the switching properties of the bilayer system resulting in phenomena analogous to an exchange-spring interaction and, leveraging added control of these interactions with an electric field, the ability to realize multistate-memory function. Such observations not only hold technological promise for ferroelectrics and multiferroics but also extend the similarities between ferromagnetic and ferroelectric materials to include the manifestation of exchange-interaction-like phenomena.

Topologically protected polar textures have provided a rich playground for the exploration of novel, emergent phenomena. Recent discoveries indicate that ferroelectric vortices and skyrmions not only host properties markedly different from traditional ferroelectrics, but also that these properties can be harnessed for unique memory devices. Using a combination of capacitor-based capacitance measurements and computational models, it is demonstrated that polar vortices in dielectric-ferroelectric-dielectric trilayers exhibit classical ferroelectric bi-stability together with the existence of low-field metastable polarization states. This behavior is directly tied to the in-plane vortex ordering, and it is shown that it can be used as a new method of non-destructive readout-out of the poled state.

Despite extensive studies on size effects in ferroelectrics, how structures and properties evolve in antiferroelectrics with reduced dimensions still remains elusive. Given the enormous potential of utilizing antiferroelectrics for high-energy-density storage applications, understanding their size effects will provide key information for optimizing device performances at small scales. Here, the fundamental intrinsic size dependence of antiferroelectricity in lead-free NaNbO3 membranes is investigated. Via a wide range of experimental and theoretical approaches, an intriguing antiferroelectric-to-ferroelectric transition upon reducing membrane thickness is probed. This size effect leads to a ferroelectric single-phase below 40 nm, as well as a mixed-phase state with ferroelectric and antiferroelectric orders coexisting above this critical thickness. Furthermore, it is shown that the antiferroelectric and ferroelectric orders are electrically switchable. First-principle calculations further reveal that the observed transition is driven by the structural distortion arising from the membrane surface. This work provides direct experimental evidence for intrinsic size-driven scaling in antiferroelectrics and demonstrates enormous potential of utilizing size effects to drive emergent properties in environmentally benign lead-free oxides with the membrane platform.

Competition between ground states at phase boundaries can lead to significant changes in properties under stimuli, particularly when these ground states have different crystal symmetries. A key challenge is to stabilize and control the coexistence of symmetry-distinct phases. Using BiFeO3 layers confined between layers of dielectric TbScO3 as a model system, we stabilize the mixed-phase coexistence of centrosymmetric and non-centrosymmetric BiFeO3 phases at room temperature with antipolar, insulating and polar semiconducting behaviour, respectively. Application of orthogonal in-plane electric (polar) fields results in reversible non-volatile interconversion between the two phases, hence removing and introducing centrosymmetry. Counterintuitively, we find that an electric field 'erases' polarization, resulting from the anisotropy in octahedral tilts introduced by the interweaving TbScO3 layers. Consequently, this interconversion between centrosymmetric and non-centrosymmetric phases generates changes in the non-linear optical response of over three orders of magnitude, resistivity of over five orders of magnitude and control of microscopic polar order. Our work establishes a platform for cross-functional devices that take advantage of changes in optical, electrical and ferroic responses, and demonstrates octahedral tilts as an important order parameter in materials interface design.

The emergence of long-range magnetic order in noncentrosymmetric compounds has stimulated interest in the possibility of exotic spin transport phenomena and topologically protected spin textures for applications in next-generation spintronics. Polar magnets, with broken symmetries of spatial inversion and time reversal, usually host chiral spin textures. This work reports on a wurtzite-structure polar magnetic metal, identified as AA′-stacked (Fe0.5Co0.5)5GeTe2, which exhibits a Néel-type skyrmion lattice as well as a Rashba-Edelstein effect at room temperature. Atomic resolution imaging of the structure reveals a structural transition as a function of Co-substitution, leading to the emergence of the polar phase at 50% Co. This discovery reveals an unprecedented layered polar magnetic system for investigating intriguing spin topologies, and it ushers in a promising new framework for spintronics.

Novel magnetic ground states have been stabilized in two-dimensional (2D) magnets such as skyrmions, with the potential next-generation information technology. Here, we report the experimental observation of a Néel-type skyrmion lattice at room temperature in a single-phase, layered 2D magnet, specifically a 50% Co-doped Fe5GeTe2 (FCGT) system. The thickness-dependent magnetic domain size follows Kittel's law. The static spin textures and spin dynamics in FCGT nanoflakes were studied by Lorentz electron microscopy, variable-temperature magnetic force microscopy, micromagnetic simulations, and magnetotransport measurements. Current-induced skyrmion lattice motion was observed at room temperature, with a threshold current density, jth = 1 × 106 A/cm2. This discovery of a skyrmion lattice at room temperature in a noncentrosymmetric material opens the way for layered device applications and provides an ideal platform for studies of topological and quantum effects in 2D.

Polar textures have attracted substantial attention in recent years as a promising analog to spin-based textures in ferromagnets. Here, using optical second-harmonic generation–based circular dichroism, we demonstrate deterministic and reversible control of chirality over mesoscale regions in ferroelectric vortices using an applied electric field. The microscopic origins of the chirality, the pathway during the switching, and the mechanism for electric field control are described theoretically via phase-field modeling and second-principles simulations, and experimentally by examination of the microscopic response of the vortices under an applied field. The emergence of chirality from the combination of nonchiral materials and subsequent control of the handedness with an electric field has far-reaching implications for new electronics based on chirality as a field-controllable order parameter.

Learning Objectives: To asynchronously connect interviewees to our residency program through a digital platform designed to recreate personalized knowledge-sharing.Background: Emergency medicine residency recruitment has continued in the virtual environment in 2021. Remote interviews limit the personalized exchange that occurs between program and applicant. Virtual interviews, while more equitable and financially feasible, result in applicants feeling less familiar with the program. To compensate, an emphasis on digital presence is needed. A well-curated website can provide foundational information about the program but typically lacks the personalized quality of an in-person on-site interview.Objectives: To asynchronously connect interviewees to our residency program through a digital platform designed to recreate personalized knowledge-sharing.Design: We created a website to convey personalized program information to 2021-2022 interviewees called the “Stanford Applicant Access Zone (SAAZ).” Through this private interviewee-only platform, we recreated many of the discussions and presentations that otherwise occur during an in-person interview. SAAZ contains interview logistics for the interview day, future engagement opportunities, videos highlighting unique features of the program, and a tour. We tracked the number of visits and page views to gauge use.Impact/Effectiveness: As of 11/23/21, there were 184 users of 210 invitees who account for 1506 page views. The peak usage was in the first week of November after invites were sent, with spikes in usage on a weekly basis thereafter, consistent with interview days. The average engagement time was 248 seconds. Apart from the welcome page, the most commonly viewed page was “Interviews” at 337 views (2.36/user), followed by “Engage” at 279 (2.18/user), “Meet the Team” at 207 (1.92/user), and “ACCEL” at 152(1.54/user). The interview day length decreased from 5 to 3 hours by relocating content to the website. SAAZ is a novel means to provide asynchronous program details while preserving personalized information sharing and shortening the virtual interview day.

Epitaxial strain has been shown to produce dramatic changes to the orbital structure in transition metal perovskite oxides and, in turn, the rate of oxygen electrocatalysis therein. Here, epitaxial strain is used to investigate the relationship between surface electronic structure and oxygen electrocatalysis in prototypical fuel cell cathode systems. Combining high-temperature electrical-conductivity-relaxation studies and synchrotron-based X-ray absorption spectroscopy studies of La0.5Sr0.5CoO3 and La0.8Sr0.2Co0.2Fe0.8O3 thin films under varying degrees of epitaxial strain reveals a strong correlation between orbital structure and catalysis rates. In both systems, films under biaxial tensile strain simultaneously exhibit the fastest reaction kinetics and lowest electron occupation in the dz2 orbitals. These results are discussed in the context of broader chemical trends and electronic descriptors are proposed for oxygen electrocatalysis in transition metal perovskite oxides.

BackgroundLeaders in graduate medical education must provide robust clinical and didactic experiences to prepare residents for independent practice. Programs traditionally create didactic experiences individually, requiring tremendous resources with variable content exposure and quality.ObjectiveWe sought to create and implement a free, open access, learner-centric, level-specific, emergency medicine (EM) residency curriculum.MethodsWe developed Foundations of Emergency Medicine (FoEM) Foundations I and II courses using Kern's model of curriculum development. Fundamental topics were identified through content guidelines from the American Board of Emergency Medicine. We incorporated learner-centric strategies into 2 flipped classroom, case-based courses targeting postgraduate year (PGY) 1 and PGY-2 residents. The curriculum was made freely available online in 2016. Faculty and resident users were surveyed annually for feedback, which informed iterative refinement of the curriculum.ResultsBetween 2016 and 2020, registration for FoEM expanded from 2 sites with 36 learners to 154 sites and 4453 learners. In 2019, 98 of 102 (96%) site leaders and 1618 of 2996 (54%) learners completed the evaluative survey. One hundred percent of responding leaders and 93% of learners were "satisfied" or "very satisfied" with FoEM content. Faculty and residents valued FoEM's usability, large volume of content, quality, adaptability, organization, resident-faculty interaction, and resident-as-teacher opportunities. Challenges to implementation included resident attendance, conference structure, technology limitations, and faculty engagement.ConclusionsWe developed and implemented a learner-centric, level-specific, national EM curriculum that has been widely adopted in the United States.

ObjectivesThe COVID-19 pandemic continues to impact health systems across the United States and worldwide in an unprecedented way; however, its influence on frontline medical trainees' educational experiences is unknown. Our objective was to determine the effects of COVID-19 on emergency medicine (EM) training programs and residents.MethodsWe performed a mixed-methods cross-sectional survey study of faculty and residents at programs registered with Foundations of Emergency Medicine. Participants completed an online survey consisting of closed and open-ended response items. We reported descriptive statistics for discrete and continuous data. Free-response data were analyzed qualitatively using a thematic approach.ResultsNinety-two percent of faculty (119/129) and 47% (1,965/4,154) of residents responded to our survey. We identified three major themes related to effects on learning: 1) impact on clinical training, 2) impact on didactic education, and 3) impact on the trainee. Nearly all residencies (96%, 111/116) allowed residents to work with patients suspected of having COVID-19, although fewer (83%, 96/115) allowed residents to intubate them. We found that 99% (1918/1928) of residents experienced virtual didactics. Faculty and trainees noted multiple educational challenges and strategies for adaptation. Trainees also expressed concerns about stress and safety.ConclusionCOVID-19 has impacted EM education in many ways including clinical training, didactic education, and trainee emotional state and concentration. Challenges and suggested solutions for learning in the virtual environment were also identified. While the pandemic continues to evolve and impact EM residents in various ways, our results may inform strategies to support medical educators and trainees during pandemics or other periods of significant disruption or crisis.

Spin-orbit torques (SOTs) that arise from materials with large spin-orbit coupling offer a new pathway for energy-efficient and fast magnetic information storage. SOTs in conventional heavy metals and topological insulators are explored extensively, while 5d transition metal oxides, which also host ions with strong spin-orbit coupling, are a relatively new territory in the field of spintronics. An all-oxide, SrTiO3 (STO)//La0.7 Sr0.3 MnO3 (LSMO)/SrIrO3 (SIO) heterostructure with lattice-matched crystal structure is synthesized, exhibiting an epitaxial and atomically sharp interface between the ferromagnetic LSMO and the high spin-orbit-coupled metal SIO. Spin-torque ferromagnetic resonance (ST-FMR) is used to probe the effective magnetization and the SOT efficiency in LSMO/SIO heterostructures grown on STO substrates. Remarkably, epitaxial LSMO/SIO exhibits a large SOT efficiency, ξ||  = 1, while retaining a reasonably low shunting factor and increasing the effective magnetization of LSMO by ≈50%. The findings highlight the significance of epitaxy as a powerful tool to achieve a high SOT efficiency, explore the rich physics at the epitaxial interface, and open up a new pathway for designing next-generation energy-efficient spintronic devices.

Two-dimensional (2D) van der Waals (vdW) magnets have recently attracted increasing attention, as they provide a novel system for exploring 2D magnetism. However, intrinsic ferromagnetism in 2D systems has almost exclusively been observed at low temperatures, limiting their technological relevance. FeNGeTe2 (N=3, 4, and 5) systems are currently becoming the most attractive 2D vdW materials due to their relatively high Curie temperatures and large saturation magnetization. However, the nature of their complex yet intriguing magnetic behaviors is still unclear, in part due to the multiple inequivalent iron sites and iron vacancies. Here, we show evolution of magnetic ordering transitions in Fe5-xGeTe2 with high Curie temperature and a strong saturation magnetization using photoemission electron microscopy and transport measurements. At 275 K, the ferromagnet transitions to a ferrimagnet, and below 110 K transitions to a state with glassy clusters. These are evidenced from temperature-dependent magnetic stripe domain evolution and anisotropic magnetoresistance measurements. Our findings show a clear magnetic ground state of Fe5-xGeTe2 at room temperature which signals that Fe5-xGeTe2 system is a very promising candidate for spintronic devices and provides a material design pathway to further increase the Curie temperature and saturation moments in vdW ferromagnets.

Two-dimensional (2D) van der Waals (vdW) magnets have recently attracted increasing attention, as they provide a novel system for exploring 2D magnetism. However, intrinsic ferromagnetism in 2D systems has almost exclusively been observed at low temperatures, limiting their technological relevance. FeNGeTe2 (N=3, 4, and 5) systems are currently becoming the most attractive 2D vdW materials due to their relatively high Curie temperatures and large saturation magnetization. However, the nature of their complex yet intriguing magnetic behaviors is still unclear, in part due to the multiple inequivalent iron sites and iron vacancies. Here, we show evolution of magnetic ordering transitions in Fe5-xGeTe2 with high Curie temperature and a strong saturation magnetization using photoemission electron microscopy and transport measurements. At 275 K, the ferromagnet transitions to a ferrimagnet, and below 110 K transitions to a state with glassy clusters. These are evidenced from temperature-dependent magnetic stripe domain evolution and anisotropic magnetoresistance measurements. Our findings show a clear magnetic ground state of Fe5-xGeTe2 at room temperature which signals that Fe5-xGeTe2 system is a very promising candidate for spintronic devices and provides a material design pathway to further increase the Curie temperature and saturation moments in vdW ferromagnets.