Memory effect of Mn5_5Ge3_3 nanomagnets embedded inside a Mn-diluted Ge matrix

Crystalline Mn5Ge3 nanomagnets are formed inside a Mn-diluted Ge matrix using Mn ion implantation. A temperature-dependent memory effect and slow magnetic relaxation are observed below the superparamagnetic blocking temperature of Mn5Ge3. Our findings corroborate that the observed spin-glass-like features are caused by the size distribution of Mn5Ge3 nanomagnets, rather than by the inter-particle interaction through the Mn-diluted Ge matrix.Comment: 10 pages, 4 figures,. submitted to Appl. Phys. Let

Ferromagnetic, structurally disordered ZnO implanted with Co ions

We present superparamagnetic clusters of structurally highly disordered Co-Zn-O created by high fluence Co ion implantation into ZnO (0001) single crystals at low temperatures. This secondary phase cannot be detected by common x-ray diffraction but is observed by high-resolution transmission electron microscopy. In contrast to many other secondary phases in a ZnO matrix it induces low-field anomalous Hall effect and thus is a candidate for magneto-electronics applications.Comment: 5 pages, 3 figure

Room temperature ferromagnetism in carbon-implanted ZnO

Unexpected ferromagnetism has been observed in carbon doped ZnO films grown by pulsed laser deposition [Phys. Rev. Lett. 99, 127201 (2007)]. In this letter, we introduce carbon into ZnO films by ion implantation. Room temperature ferromagnetism has been observed. Our analysis demonstrates that (1) C-doped ferromagnetic ZnO can be achieved by an alternative method, i.e. ion implantation, and (2) the chemical involvement of carbon in the ferromagnetism is indirectly proven.Comment: 13 pages, 3 figs, accepted for publication at Appl. Phys. Let

Data publication : Tailoring crosstalk between localized 1D spin-wave nanochannels using focused ion beams

This dataset contains raw data (SEM images, AFM, FMR, BLS, TetraX) used to study the dynamical edge modes in closely spaced permalloy microstrips

Visible light actuated efficient exclusion between plasmonic Ag/AgCl micromotors and passive beads

Insight is provided into the collective behavior of visible‐light photochemically driven plasmonic Ag/AgCl Janus particles surrounded by passive polystyrene (PS) beads. The active diffusion of single Janus particles and their clusters (small: consisting of two or three Janus particles and large: consisting of more than ten Janus particles), and their interaction with passive PS beads, are analyzed experimentally and in simulations. The diffusivity of active Janus particles, and thus the exclusive effect to passive PS beads, can be regulated by the number of single Janus particles in the cluster. On the simulation side, the Langevin equations of motion for self‐propelled Janus particles and diffusing passive PS beads are numerically solved using Molecular‐Dynamics simulations. The complex interactions of both subsystems, including elastic core‐to‐core interactions, short‐range attraction, and effective repulsion due to light‐induced chemical reactions are considered. This complex mixed system not only provides insight to the interactive effect between active visible light‐driven self‐propelled micromotors and passive beads, but also offers promise for implications in light‐controlled propulsion transport and chemical sensing.Visible light actuated plasmonic Ag/AgCl‐based spherical Janus micromotors reveal efficient exclusion effects on surrounding passive beads in pure H2O. The exclusion efficiency is controlled by the number of single Janus particles composing micromotors. The system‐specific interaction parameter between Janus micromotors and passive beads is determined. It assures predictive power for further theoretical analysis of the complex dynamics of these heterogeneous active‐passive systems.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146656/1/smll201802537_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146656/2/smll201802537.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146656/3/smll201802537-sup-0001-S1.pd

Magneto-structural correlations in a systematically disordered B2 lattice

Ferromagnetism in certain B2 ordered alloys such as Fe(60)Al(40)can be switched on, and tuned, via antisite disordering of the atomic arrangement. The disordering is accompanied by a similar to 1 % increase in the lattice parameter. Here we performed a systematic disordering of B2 Fe(60)Al(40)thin films, and obtained correlations between the order parameter (S), lattice parameter (a(0)), and the induced saturation magnetization (M-s). As the lattice is gradually disordered, a critical point occurs at 1 -S= 0.6 anda(0)= 2.91 angstrom, where a sharp increase of theM(s)is observed. DFT calculations suggest that below the critical point the system magnetically behaves as it would still be fully ordered, whereas above, it is largely the increase ofa(0)in the disordered state that determines theM(s). The insights obtained here can be useful for achieving tailored magnetic properties in alloys through disordering

Point-of-care laboratory halves door-to-therapy-decision time in acute stroke

Currently, stroke laboratory examinations are usually performed in the centralized hospital laboratory, but often planned thrombolysis is given before all results are available, to minimize delay. In this study, we examined the feasibility of gaining valuable time by transferring the complete stroke laboratory workup required by stroke guidelines to a point-of-care laboratory system, that is, placed at a stroke treatment room contiguous to the computed tomography, where the patients are admitted and where they obtain neurological, laboratory, and imaging examinations and treatment by the same dedicated team. Our results showed that reconfiguration of the entire stroke laboratory analysis to a point-of-care system was feasible for 200 consecutively admitted patients. This strategy reduced the door-to-therapy-decision times from 84 ± 26 to 40 ± 24 min (p < 0.001). Results of most laboratory tests (except activated partial thromboplastin time and international normalized ratio) revealed close agreement with results from a standard centralized hospital laboratory. These findings may offer a new solution for the integration of laboratory workup into routine hyperacute stroke management