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JTRF2020 is the latest TRF solution computed at JPL by assimilating frame input data submitted by the IVS, IGS, ILRS, and IDS for ITRF2020. JTRF2020, determined with a square-root information filter and Dyer-McReynolds s moother algorithm, adopts a time-series based representation: Its daily time series determined from observations of a multi-technique space-geodetic network of 931 stations describe, through their Cartesian coordinates, the deformation of solid Earth as a function of time. Such coordinates are inherently expressed in Earth’s Center of Mass as sensed by SLR and give access to the quasi-instantaneous scale implied by the underlying frame. JTRF2020, like its predecessor JTRF2014, traditionally adopts a scale relying on VLBI and SLR observations only. In this presentation, we will describe the process we adopted to define and construct JTRF2020, and will discuss metrics constructed to assess the frame quality., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Classical interferometers are indispensable tools for the precise determination of various physical quantities. Their accuracy is bound by the standard quantum limit. This limit can be overcome by using quantum states or nonlinear quantum elements. Here, we present the experimental study of a nonlinear Josephson interferometer operating in the microwave regime. Our quantum microwave parametric interferometer (QUMPI) is based on superconducting flux-driven Josephson parametric amplifiers combined with linear microwave elements. We perform a systematic analysis of the implemented QUMPI. We find that its Gaussian interferometric power exceeds the shot-noise limit and observe sub-Poissonian photon statistics in the output modes. Furthermore, we identify a low-gain operation regime of the QUMPI which is essential for optimal quantum measurements in quantum illumination protocols., Comment: 6 pages, 5 figures

We investigate the growth conditions for thin (less than 200 nm) sputtered aluminum (Al) films. These coatings are needed for various applications, e.g. for advanced manufacturing processes in the aerospace industry or for nanostructures for quantum devices. Obtaining high-quality films, with low roughness, requires precise optimization of the deposition process. To this end, we tune various sputtering parameters such as the deposition rate, temperature, and power, which enables 50 nm thin films with a root mean square (RMS) roughness of less than 1 nm and high reflectivity. Finally, we confirm the high quality of the deposited films by realizing superconducting single-photon detectors integrated into multi-layer heterostructures consisting of an aluminum mirror and a silicon dioxide dielectric spacer. We achieve an improvement in detection efficiency at 780 nm from 40 % to 70 % by this integration approach., Comment: 11 pages, 6 figures

The net employment impacts of a renewable energy or energy efficiency investment account both for jobs that are created, as well as jobs that might be displaced in other parts of the economy as a result of the investment. This report therefore addresses the following research question: How many jobs can be created by policy support for investment in low carbon energy and energy efficiency compared to supporting fossil fuel incumbents? The review identifies a variety of approaches used to estimate the quantity of low carbon energy job creation. It finds that much greater standardisation of methods would be desirable in order to compare how many jobs can be created by policies supporting low carbon energy and energy efficiency, both at a project scale and a wider societal level. Our findings also underline a relative lack of metrics and data measuring quality, skills, and geographic distribution of low carbon job creation, and these should be priority areas for further research.

To describe how social disruptions caused by the COVID-19 pandemic impacted child access to healthcare and child health behaviors in 2020. We used mixed-methods to conduct surveys and in-depth interviews with English- and Spanish-speaking parents of young children from five geographic regions in the USA. Participants completed the COVID-19 Exposure and Family Impact Survey (CEFIS). Semistructured telephone interviews were conducted between August and October 2020. Of the 72 parents interviewed, 45.8% of participants were Hispanic, 20.8% Black (non-Hispanic), and 19.4% White (non-Hispanic). On the CEFIS, the average (SD) number of social/family disruptions reported was 10.5 (3.8) out of 25. Qualitative analysis revealed multiple levels of themes that influenced accessing healthcare during the pandemic, including two broad contextual themes: (a) lack of trustworthiness of medical system/governmental organizations, and (b) uncertainty due to lack of consistency across multiple sources of information. This context influenced two themes that shaped the social and emotional environments in which participants accessed healthcare: (a) fear and anxiety and (b) social isolation. However, the pandemic also had some positive impacts on families: over 80% indicated that the pandemic made it "a lot"or "a little"better to care for their new infants. Social and family disruptions due to COVID-19 were common. These disruptions contributed to social isolation and fear, and adversely impacted multiple aspects of child and family health and access to healthcare. Some parents of infants reported improvements in specific health domains such as parenting, possibly due to spending more time together.

Research into variable pitch propeller (VPP) quadcopters has seen a marked increase in recent years which is due to their enhanced dynamic capabilities compared to conventional fixed pitch propeller quadcopters. Adding actuators to control the pitch angles of the propellers increases the mechanical complexity and hence may increase the risk of faults. In this paper, the flight control of a centrally-powered VPP quadcopter in the presence of a propeller fault is studied. This problem has not been studied in the literature. In this paper firstly the balance trajectory is analysed. The uncontrollable mode is identified next. Finally, a linear controller is proposed. It is shown that the yaw angle and angular velocity become uncontrollable in the presence of a VPP fault, yet the quadcopter can still accurately track a desired trajectory. It is also discovered that the quadcopter exhibits different and favourable behaviour, such as slow self-spinning speed. The relationship under certain parameter conditions is analysed and the parameter conditions that lead to zero self-spinning are identified. Our analysis could contribute to the development of high-performance quadcopters that are both agile and robust with respect to faults. Simulation results are presented to verify the theoretical findings.

Hintergrund und Stand (inter)nationaler Forschung: Orale Mikroorganismen können mit einer signifikanten Anzahl an Malignomentitäten in Verbindung gebracht werden. Nur 1/3 der PatientInnen, welche die Diagnose Bauchspeicheldrüsenkrebs erhalten, überleben noch ein Jahr. Fragestellung [zum vollständigen Text gelangen Sie über die oben angegebene URL]

6 pages, 4 figures, supplemental material enclosed; International audience; We find that the N\'eel state of the layered organic conductor $\kappa$-(BETS)$_2$FeBr$_4$ shows no spin modulation of the Shubnikov-de Haas oscillations, contrary to the paramagnetic state of the same material. This is evidence of spin degeneracy of Landau levels -- a direct manifestation of the generic Zeeman spin-orbit coupling, predicted for antiferromagnetic conductors. Likewise, we find no spin modulation in the angle dependence of the slow Shubnikov-de Haas oscillations in the optimally electron-doped cuprate Nd$_{2-x}$Ce$_x$CuO$_4$. This points to the presence of N\'eel order in this superconductor even at optimal doping.

We experimentally demonstrate the formation of room-temperature skyrmions with radii of about 25 nm in easy-plane anisotropy multilayers with an interfacial Dzyaloshinskii-Moriya interaction (DMI). We detect the formation of individual magnetic skyrmions by magnetic force microscopy and find that the skyrmions are stable in out-of-plane fields up to about 200 mT. We determine the interlayer exchange coupling as well as the strength of the interfacial DMI. Additionally, we investigate the dynamic microwave spin excitations by broadband magnetic resonance spectroscopy. From the uniform Kittel mode we determine the magnetic anisotropy and lowdamping α < 0.04. We also find clear magnetic resonance signatures in the nonuniform (skyrmion) state. Our findings demonstrate that skyrmions in easy-plane multilayers are promising for spin-dynamical applications.

Heating in residential, commercial and industrial settings makes up almost half of final energy consumption in the UK, more than the energy consumed for electricity or transport. The electrification of heat is anticipated to play a major role for the UK’s efforts to reduce emissions to net-zero by 2050. Heating demand is highly variable between seasons and time of day. To take maximum advantage of low-carbon generation, and to respect the limitations of the distribution grid, electricity loads for heating will need to be flexible. This Briefing Paper explores the potential for smart flexible low-carbon electric heating in UK homes and the challenges for consumer engagement. This paper considers four key elements for enabling smart, flexible and cost- effective electric heating in UK homes: low-carbon heating systems; cost-reflective electricity pricing; thermally efficient buildings; and smart storage devices.

Introduction The complex etiology of autism spectrum disorder (ASD) is still unresolved. Preterm birth (, Martina Persson and co-workers study autism spectrum disorder and gestational age in three Nordic countries., Author summary Why was this study done? Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by persistent impairments in social communication and restricted and repetitive behaviors. The etiology remains unresolved. Length of gestation, including preterm birth, has been linked to risk of ASD, but reliable estimates of risks for the whole range of gestational ages (GAs) are lacking. The primary objective of this study was to provide a detailed and robust description of ASD risk across the entire range of GA while taking fetal sex and size at birth into account. What did the researchers do and find? This study was based on population-based data from national medical registries in three Nordic countries—Sweden, Finland, and Norway—and included 3,526,174 singletons born 1995 to 2015. Relative risks (RRs) of ASD by GA at birth were estimated with log binominal regression. The RR of ASD increased by each week of GA, pre- as well as postterm, from 40 to 24 weeks of gestation and from 40 to 44 weeks of gestation, independently of sex and birth weight for GA. What do these findings mean? On a population level, the risks of ASD were increased in children born either pre- or postterm, including children born close to week 40. We found that the risk of ASD increased weekly, with each week further away from 40 weeks of gestation.

The low-noise amplification of weak microwave signals is crucial for countless protocols in quantum information processing. Quantum mechanics sets an ultimate lower limit of half a photon to the added input noise for phase-preserving amplification of narrowband signals, also known as the standard quantum limit (SQL). This limit, which is equivalent to a maximum quantum efficiency of $0.5$, can be overcome by employing nondegenerate parametric amplification of broadband signals. We show that, in principle, a maximum quantum efficiency of 1 can be reached. Experimentally, we find a quantum efficiency of $0.69 \pm 0.02$, well beyond the SQL, by employing a flux-driven Josephson parametric amplifier and broadband thermal signals. We expect that our results allow for fundamental improvements in the detection of ultraweak microwave signals.

Swarm robotics investigates groups of relatively simple robots that use decentralized control to achieve a common goal. While the robots of many swarm systems communicate via optical links, the underlying channels and their impact on swarm performance are poorly understood. This paper models the optical channel of a widely used robotic platform, the e-puck. It proposes SwarmCom, a mobile ad-hoc network for mobile robots. SwarmCom has a detector that, with the help of the channel model, was designed to adapt to the environment and nearby robots. Experiments with groups of up to 30 physical e-pucks show that (i) SwarmCom outperforms the state-of-the-art infra-red communication software—libIrcom—in range (up to 3 times further), bit error rate (between 50 and 63% lower), or throughput (up to 8 times higher) and that (ii) the maximum number of communication channels per robot is relatively low, which limits the load per robot even for high-density swarms. Using channel coding, the bit error rate can be further reduced at the expense of throughput. SwarmCom could have profound implications for swarm robotics, contributing to system understanding and reproducibility, while paving the way for novel applications.

The volume collects papers submitted to Pure and Applied Geophysics following a call on the topic “Geodynamics and Earth Tides”. Partly, the authors had participated in the 18th Geodynamics and Earth Tides Symposium held in Trieste, Italy, in June 2016. The Earth tides constitute the leading thread through the book, since instrumentation sensitive enough to observe them, also records a broad spectrum of signals generated by Earth dynamic processes.

This volume aims at conveying the rich and interdisciplinary topics discussed at the 18th Geodynamics and Earth Tides Symposium, Trieste, 2016. For seventeen times the gathering was named the Earth Tides Symposium, when giving tribute to the evolution of the observed signals, the term geodynamics was added to the title.The present volume aims at a full coverage of the Symposium by including the entire list of abstracts that were presented either as oral or poster presentations

Patients diagnosed with epilepsy experience cognitive dysfunction that may be due to a transient cognitive/memory impairment (TCI/TMI) caused by spontaneous epileptiform spikes. We asked in a cohort of 166 adult patients with medically refractory focal epilepsy if spikes in specific neuroanatomical regions during verbal episodic memory encoding would significantly decrease the probability of recall. We found using a na��ve Bayesian machine learning model that the probability of correct word recall decreased significantly by 11.9% when spikes occurred in left Brodmann area 21 (BA)21, (p, All of the co-authors of this article agree to withdraw it, because it is not ready yet for its submission

Recent climate change initiatives, such as ‘Mission Innovation’ launched alongside the Paris Agreement in 2015, urge redoubled research into innovative low carbon technologies. However, climate change is an urgent problem – emissions reductions must take place rapidly throughout the coming decades. This raises an important question: how long might it take for individual technologies to emerge from research, find market opportunities and make a tangible impact on emissions reductions? Here, we consider historical evidence for the time a range of energy supply and energy end-use technologies have taken to emerge from invention, diffuse into the market and reach widespread deployment. We find considerable variation, from 20 to almost 70 years. Our findings suggest that the time needed for new technologies to achieve widespread deployment should not be overlooked, and that innovation policy should focus on accelerating the deployment of existing technologies as well as research into new ones.

Introduction: The predictors of poor outcome (POPO) have received increasing attention in the last few years. These are criteria that indicate a poor disease course for pediatric patients with Crohn’s Disease. For ulcerative colitis, no POPO criteria have been established so far. The aim of this[for full text, please go to the a.m. URL], 63. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e.V. (GMDS)

We present experimental control of the magnetic anisotropy in a gadolinium iron garnet (GdIG) thin film from in-plane to perpendicular anisotropy by simply changing the sample temperature. The magnetic hysteresis loops obtained by SQUID magnetometry measurements unambiguously reveal a change of the magnetically easy axis from out-of-plane to in-plane depending on the sample temperature. Additionally, we confirm these findings by the use of temperature dependent broadband ferromagnetic resonance spectroscopy (FMR). In order to determine the effective magnetization, we utilize the intrinsic advantage of FMR spectroscopy which allows to determine the magnetic anisotropy independent of the paramagnetic substrate, while magnetometry determines the combined magnetic moment from film and substrate. This enables us to quantitatively evaluate the anisotropy and the smooth transition from in-plane to perpendicular magnetic anisotropy. Furthermore, we derive the temperature dependent $g$-factor and the Gilbert damping of the GdIG thin film.

We investigate synchronization in a population of mobile pulse-coupled agents with a view towards\ud implementations in swarm robotics systems and mobile sensor networks. Previous theoretical\ud approaches dealt with range and nearest neighbor interactions. In the latter case, a synchronization-hindering\ud regime for intermediate agent mobility was found. In the present work, we investigate\ud the robustness of this intermediate regime under practical scenarios. We show that synchronization\ud in the intermediate regime can be predicted by means of a suitable metric of the phase response\ud curve. Furthermore, we study more realistic K-nearest neighbors and cone of vision interactions,\ud showing that it is possible to control the extent of the synchronization-hindering region by appropriately\ud tuning the size of the neighborhood. To assess the effect of noise, we analyze the\ud propagation of perturbations over the network and draw an analogy between the response in the\ud hindering regime and stable chaos. Our findings reveal the conditions for the control of clock or\ud activity synchronization of agents with intermediate mobility. In addition, the emergence of the\ud intermediate regime is validated experimentally using a swarm of physical robots interacting with\ud cone of vision interactions.\ud

Maimouna Ndiaye,1,2 Peter Nyasulu,1 Hoang Nguyen,6,7 Elizabeth D Lowenthal,8,9 Robert Gross,10 Edward J Mills,3 Jean B Nachega4–6 1School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 2Central Medical Stores, Ministry of Health, Gaborone, Botswana; 3Faculty of Health Sciences, University of Ottawa, Ottawa, Canada; 4Department of Medicine and Centre for Infectious Diseases, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; 5Department of Epidemiology, Infectious Disease Epidemiology Research Program, Pittsburgh University Graduate School of Public Health, Pittsburgh, PA, USA; 6Departments of Epidemiology and International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; 7Tay Ho Clinics, Department of Medicine, Hanoi Health Services, Hanoi, Vietnam; 8Departments of Pediatrics and Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA; 9Center for Pediatric Clinical Effectiveness, Children’s Hospital of Philadelphia, Philadelphia, PA, USA; 10Departments of Medicine and Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA Objective: Little is known about factors associated with suboptimal antiretroviral treatment (ART) adherence among adolescents in Sub-Saharan Africa. Our objective was to determine the level of ART adherence and predictors of non-adherence among human immunodeficiency virus (HIV)-infected adolescents at the Botswana-Baylor Children's Clinical Centre of Excellence in Gaborone, Botswana. Methods: In a cross-sectional study, 82 HIV-infected adolescents receiving ART and their caregivers were administered a structured questionnaire. The patient's clinical information was retrieved from medical records. Outcome measures included excellent pill count ART adherence (>95%) and virologic suppression (HIV viral load

International audience

Endotherms such as rats and mice huddle together to keep warm. The huddle is considered to be an example of a self-organising system, because complex properties of the collective group behaviour are thought to emerge spontaneously through simple interactions between individuals. Groups of rodent pups display two such emergent properties. First, huddling undergoes a ‘phase transition’, such that pups start to aggregate rapidly as the temperature of the environment falls below a critical temperature. Second, the huddle maintains a constant ‘pup flow’, where cooler pups at the periphery continually displace warmer pups at the centre. We set out to test whether these complex group behaviours can emerge spontaneously from local interactions between individuals. We designed a model using a minimal set of assumptions about how individual pups interact, by simply turning towards heat sources, and show in computer simulations that the model reproduces the first emergent property—the phase transition. However, this minimal model tends to produce an unnatural behaviour where several smaller aggregates emerge rather than one large huddle. We found that an extension of the minimal model to include heat exchange between pups allows the group to maintain one large huddle but eradicates the phase transition, whereas inclusion of an additional homeostatic term recovers the phase transition for large huddles. As an unanticipated consequence, the extended model also naturally gave rise to the second observed emergent property—a continuous pup flow. The model therefore serves as a minimal description of huddling as a self-organising system, and as an existence proof that group-level huddling dynamics emerge spontaneously through simple interactions between individuals. We derive a specific testable prediction: Increasing the capacity of the individual to generate or conserve heat will increase the range of ambient temperatures over which adaptive thermoregulatory huddling will emerge.

International audience

Chemokine ligand 2 (CCL2) mediates chemotaxis of monocytes to inflammatory sites via interaction with its G protein-coupled receptor CCR2. Preclinical animal models suggest that the CCL2-CCR2 axis has a critical role in the development and maintenance of inflammatory disease states (e.g., multiple sclerosis, atherosclerosis, insulin resistance, restenosis, and neuropathic pain), which can be treated through inhibition of the CCR2 receptor. However, in clinical trials high-affinity inhibitors of CCR2 have often demonstrated a lack of efficacy. We have previously described a new approach for the design of high-affinity CCR2 antagonists, by taking their residence time (RT) on the receptor into account. Here, we report our findings on both structure-affinity relationship (SAR) and structure-kinetic relationship (SKR) studies for a series of 3-((inden-1-yl)amino)-1-isopropyl-cyclopentane-1-carboxamides as CCR2 antagonists. SAR studies showed that this class of compounds tolerates a vast diversity of substituents on the indenyl ring with only small changes in affinity. However, the SKR is affected greatly by minor modifications of the structure. The combination of SAR and SKR in the hit-to-lead process resulted in the discovery of a new high-affinity and long-residence-time CCR2 antagonist (compound 15a, Ki = 2.4 nM; RT = 714 min).

International audience

Two critical points have been revealed in the normal-state phase diagram of the electron-doped cuprate superconductor Nd2−xCexCuO4 by exploring the Fermi surface properties of high-quality single crystals by high-field magnetotransport. First, the quantitative analysis of the Shubnikov-de Haas effect shows that the weak superlattice potential responsible for the Fermi surface reconstruction in the overdoped regime extrapolates to zero at the doping level xc = 0.175 corresponding to the onset of superconductivity. Second, the high-field Hall coefficient exhibits a sharp drop right below optimal doping xopt = 0.145 where the superconducting transition temperature is maximum. This drop is most likely caused by the onset of long-range antiferromagnetic ordering. Thus the superconducting dome appears to be pinned by two critical points to the normal state phase diagram.

Geodetic observations of the Earth’s gravity field, shape, and rotation and their changes in time (the three fundamental areas of geodesy)capture the signals of variation in the entire fluid envelope of the solid Earth, including the terrestrial water storage. Therefore, the Global Geodetic Observing System (GGOS) has the capability to monitor mass transport particularly in the global water cycle. The IGCP 565 Project aims to utilize this potential and to develop GGOS into a monitoring system for the hydrological cycle on global to regional scales. Key scientific issues addressed are: (1) Development of an integrated dynamic model for the predictions of the geodetic signals of daily to interannual surface mass changes, (2) Inversion algorithms for integrated geodetic observations for surface mass changes; (3) Assimiltion of observed surface mass changes in hydrological models; and (4) Development of products relevant for regional water management. The project supports capacity building in space-geodetic data processing, modeling of the hydrological cycle, and interpretation of the observations in terms of terrestrial water storage. A focus is on products for regional water management, particularly in developing countries. Coordination of the research and capacity building is provided through a series of five annual workshops.

Background\ud \ud Contemporary antiretroviral treatment regimens are simpler than in the past, with lower pill burden and once-daily dosing frequency common. We performed a meta-analysis of randomized controlled trials (RCTs) to investigate the impact of pill burden and once-daily vs twice-daily dosing on ART adherence and virological outcomes.\ud \ud Methods\ud \ud A literature search of 4 electronic databases through 31 March 2013 was used. RCTs comparing once-daily vs twice-daily ART regimens that also reported on adherence and virological suppression were included. Study design, study population characteristics, intervention, outcome measures, and study quality were extracted. Study quality was rated using the Cochrane risk-of-bias tool.\ud \ud Results\ud \ud Nineteen studies met our inclusion criteria (N = 6312 adult patients). Higher pill burden was associated with both lower adherence rates (P = .004) and worse virological suppression (P < .0001) in both once-daily and twice-daily subgroups, although the association with adherence in the once-daily subgroup was not statistically significant. The average adherence was modestly higher in once-daily regimens than twice-daily regimens (weighted mean difference = 2.55%; 95% confidence interval [CI], 1.23 to 3.87; P = .0002). Patients on once-daily regimens did not achieve virological suppression more frequently than patients on twice-daily regimens (relative risk [RR] = 1.01; 95% CI, 0.99 to 1.03; P = .50). Both adherence and viral load suppression decreased over time, but adherence decreased less with once-daily dosing than with twice-daily dosing.\ud \ud Conclusions\ud \ud Lower pill burden was associated with both better adherence and virological suppression. Adherence, but not virological suppression, was slightly better with once- vs twice-daily regimens.

Two critical points have been revealed in the normal-state phase diagram of the electron-doped cuprate superconductor Nd$_{2-x}$Ce$_x$CuO$_4$ by exploring the Fermi surface properties of high quality single crystals by high-field magnetotransport. First, the quantitative analysis of the Shubnikov-de Haas effect shows that the weak superlattice potential responsible for the Fermi surface reconstruction in the overdoped regime extrapolates to zero at the doping level $x_c = 0.175$ corresponding to the onset of superconductivity. Second, the high-field Hall coefficient exhibits a sharp drop right below optimal doping $x_{\mathrm{opt}} = 0.145$ where the superconducting transition temperature is maximum. This drop is most likely caused by the onset of long-range antiferromagnetic ordering. Thus, the superconducting dome appears to be pinned by two critical points to the normal state phase diagram., Comment: 9 pages; 7 figures; 1 table

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During the past years there has been renewed interest in the wide-bandgap II-VI semiconductor ZnO, triggered by promising prospects for spintronic applications. First, ferromagnetism was predicted for dilute magnetic doping. In comprehensive investigation of ZnO:Co thin films based on the combined measurement of macroscopic and microscopic properties, we find no evidence for carrier-mediated itinerant ferromagnetism. Phase-pure, crystallographically excellent ZnO:Co is uniformly paramagnetic. Superparamagnetism arises when phase separation or defect formation occurs, due to nanometer-sized metallic precipitates. Other compounds like ZnO:(Li,Ni) and ZnO:Cu do not exhibit indication of ferromagnetism. Second, its small spin-orbit coupling and correspondingly large spin coherence length makes ZnO suitable for transporting or manipulating spins in spintronic devices. From optical pump/optical probe experiments, we find a spin dephasing time of the order of 15 ns at low temperatures which we attribute to electrons bound to Al donors. In all-electrical magnetotransport measurements, we successfully create and detect a spin-polarized ensemble of electrons and transport this spin information across several nanometers. We derive a spin lifetime of 2.6 ns for these itinerant spins at low temperatures, corresponding well to results from an electrical pump/optical probe experiment., 11 pages, 6 figures, 99 references

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We report anisotropic magnetoresistance in Pt|Y3Fe5O12 bilayers. In spite of Y3Fe5O12 being a very good electrical insulator, the resistance of the Pt layer reflects its magnetization direction. The effect persists even when a Cu layer is inserted between Pt and Y3Fe5O12, excluding the contribution of induced equilibrium magnetization at the interface. Instead, we show that the effect originates from concerted actions of the direct and inverse spin Hall effects and therefore call it “spin Hall magnetoresistance.”

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Coupled superconducting transmission line resonators have applications in quantum information processing and fundamental quantum mechanics. A particular example is the realization of fast beam splitters, which however is hampered by two-mode squeezer terms. Here, we experimentally study superconducting microstrip resonators which are coupled over one third of their length. By varying the position of this coupling region we can tune the strength of the two-mode squeezer coupling from 2.4% to 12.9% of the resonance frequency of 5.44GHz. Nevertheless, the beam splitter coupling rate for maximally suppressed two-mode squeezing is 810MHz, enabling the construction of a fast and pure beam splitter.

The quantitative understanding of converse magnetoelectric effects, i.e., the variation of the magnetization as a function of an applied electric field, in extrinsic multiferroic hybrids is a key prerequisite for the development of future spintronic devices. We present a detailed study of the strain-mediated converse magnetoelectric effect in ferrimagnetic Fe3O4 thin films on ferroelectric BaTiO3 substrates at room temperature. The experimental results are in excellent agreement with numerical simulation based on a two-region model. This demonstrates that the electric field induced changes of the magnetic state in the Fe3O4 thin film can be well described by the presence of two different ferroelastic domains in the BaTiO3 substrate, resulting in two differently strained regions in the Fe3O4 film with different magnetic properties. The two-region model allows to predict the converse magnetoelectric effects in multiferroic hybrid structures consisting of ferromagnetic thin films on ferroelastic substrates.