We demonstrate electrical spin injection from ferromagnetic Fe/Tb multilayer structures with remanent perpendicular magnetization into GaAs-based light-emitting diodes at room temperature. Using a reverse-biased Schottky contact and MgO tunnel contact, respectively, we achieve remanence. The maximum degree of circular polarization the emitted light is 3%

We demonstrate electrical spin injection into a (GaIn)As∕GaAs light-emitting diode from the remanent state of ferromagnetic contacts in perpendicular geometry. Using Fe∕Tb multilayer structure with magnetic anisotropy and reverse-biased Schottky contact, we achieve circular polarization degree emitted light 0.75% at 90K.

ZnO(0001) substrates were ion implanted with 100 keV of Co and 300 Gd at different fluences ranging from 5×1013–1×1015/cm2. The resulting Co:ZnO Gd:ZnO samples analyzed respect to their structural, magnetic, optical properties. effect annealing 350 °C on the structure magnetic properties investigated as well. For hardly any changes observable, neither in structural nor properties, even though existence substitutional Co2+ ZnO lattice could be shown by means low temperature photoluminescence...

We demonstrate a photodetector with ferromagnetic contacts which can electrically detect the polarization degree of incoming light using spin filtering photoinduced spin-polarized electron currents. Our structure is pin diode single GaAs quantum well as active region and Fe∕Tb multilayer on top MgO tunnel barrier n-contact where current filtered. The photocurrent depends magnetization injected light. prove that even in remanence at room temperature circular incident be unambiguously...

We study the disorder dependence of phase coherence time quasi-one-dimensional wires and two-dimensional (2D) Hall bars fabricated from a high mobility GaAs/AlGaAs heterostructure. Using an original ion implantation technique, we can tune intrinsic felt by 2D electron gas continuously vary system semiballistic regime to localized one. In diffusive regime, follows power law as function diffusion coefficient expected in Fermi-liquid theory, without any sign low-temperature saturation....

High-efficient ZnO-based nanorod array light-emitting diodes (LEDs) were grown by an oblique-angle deposition scheme. Due to the shadowing effect, inclined ZnO vapor-flow was selectively deposited on tip surfaces of pre-fabricated p-GaN arrays, resulting in formation nanosized heterojunctions. The LED architecture composed slanted n-ZnO film arrays exhibits a well-behaving current rectification junction diode with low turn-on voltage 4.7 V, and stably emits bluish-white luminescence dominant...

This study reports the preparation of self-organized 1-dimensional magnetic structures Fe on Al2O3 (0001) by oblique deposition. The x-ray diffraction (XRD) results in this show preferred (110) texture films. XRD and extended adsorption fine structure measurements indicate larger deposition angle (65°) leads to more disorder crystalline structure. After capping with a Pd overlayer, Pd/Fe/Al2O3 still exhibits uniaxial anisotropy induced underlying nanostructure. changes variation thickness...

Abstract The kinematics of hydrogen diffusion in nontransparent metallic materials is crucial to the hydrogen-sensing and -storage technology remains a challenge. Alongside conventional optical investigations, absorption-induced reversible changes magnetic properties ferromagnetic thin films provides new method for visualization solids. Here we monitor real-time cobalt-palladium alloy (Co 25 Pd 75 ) film using magneto-optical Kerr microscope. spatially resolved contrasted images provide...

Zinc-blende GaN layers grown by molecular beam epitaxy were uniformly focused-ion-beam implanted with 300keV Gd3+ ions for doses ranging from 1×1012to1×1015cm−2, and their structural magnetic properties studied. The samples not subjected to any annealing treatment. Only Gd incorporation into zinc-blende was observed x-ray diffraction. Magnetic investigations using superconducting quantum interference device magnetometry reveal a (super)paramagneticlike behavior an ordering temperature around...

The magnetooptical Faraday rotations of epitaxial films Bi x Y 3- Fe 5 O 12 (Bi:YIG) grown on [111]-oriented gadolinium gallium garnet (GGG) substrates by pulsed laser deposition (PLD) were studied with bismuth content = 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0. rotation angles, θ F , the measured method rotating analyzer ellipsometry (RAE) photon energy varied from 1.5 to 3.5 eV. It was shown that in addition increase increasing peaks shifted toward red region as changed 1.0 1.5. peak positions for...

Single (Co/Pt)_{7} multilayer nanowires prepared by electron beam lithography with perpendicular magnetic anisotropy are locally modified means of Ga-ion implantation generating 180 degrees domain walls which pinned at the edges underlying thin Pt wires. Since we can exclude contributions from anisotropic and Lorentz magnetoresistance this allows us to determine resistance a single wall room temperature. We find positive relative increase DeltaR/R=1.8% inside agrees well model Levy Zhang...

We analyze the electrical injection of spin-polarized electrons into a (GaIn)As∕GaAs light-emitting diode. Using an Fe∕Tb multilayer structure with perpendicular magnetic anisotropy and reverse-biased Schottky contact, we demonstrate spin even in remanence between 90 260K. The maximum degree circular polarization emitted light is 0.75% at 90K.

Dysprosium(Dy)-doped zinc oxide (Dy:ZnO) thin films were fabricated on c-oriented sapphire substrate by pulsed-laser deposition with doping concentration ranging from 1 to 10 at. %. X-ray diffraction (XRD), Raman-scattering, optical transmission spectroscopy, and spectroscopic ellipsometry revealed incorporation of Dy into ZnO host matrix without secondary phase. Solubility limit in under our condition was between 5 % according XRD Raman-scattering characteristics. Optical spectroscopy also...

We present phase coherence time measurements in quasi-one-dimensional mesoscopic wires made from high mobility two-dimensional electron gas. By implanting gallium ions into a GaAs/AlGaAs heterojunction we are able to vary the diffusion coefficient over 2 orders of magnitude. show that diffusive limit, decoherence follows power law as function expected by theory. When disorder is low enough so samples semiballistic, observe new and unexpected regime which independent disorder. In addition,...

In this study, the magnetic coercivity (Hc) of Fe/ZnO heterostructure was significantly enhanced by 2–3 times after applying a suitable current. This Hc enhancement originates from Fe-oxidation at interface induced direct current heating. Depth-profiling X-ray photoemission spectroscopy analysis confirmed formation FeO, Fe3O4, and Fe2O3 close to region, depending on Fe thickness annealing process. study demonstrates that heating can moderately change local oxidation modulate properties....

The hydrogenation induced change of magneto-optical Kerr effect (MOKE) was studied in n ML Pd/30 Fe bilayers on Al2O3(0001). With the increasing Pd thickness from 3 to 60 ML, MOKE extinction angle gradually shifted by 0.6° and enhancement intensity reached 35%–40% after exposure 1 atm hydrogen. reversibility this significant demonstrated cyclic desorption reabsorption This study reveals sensitive MO response combination a magnetic thin film with highly hydrogenated capping layer.

In this study, the magnetic coercivity (Hc) of Fe/ZnO heterostructure monotonically decreased as voltage was applied. The reversibility effect demonstrated by cyclically changing bias from 0 to 6–9 V; Hc 15%–20%. value exhibited same variation whether applied positive or negative. As thick Fe-oxide gradually formed at interface using direct current heating, increased and a similar voltage-induced reduction Hc.

Hydrogenation-induced modification of magnetic properties has been widely studied. A Mg spacer layer with high hydrogen storage stability was clamped in a Pd/Co/Mg/Fe multilayer structure to enhance its and explore the structure's magneto-transport properties. After 1 bar exposure, formation stable MgH2 phase demonstrated an ambient environment at room temperature through X-ray diffraction. Lower coupling enhanced magnetoresistance, compared those as-grown sample, were observed using...

Oxygen vacancy is the most studied point defect and has been found to significantly influence physical properties of zinc oxide (ZnO). By using atomic force microscopy (AFM), we show that frictional on ZnO surface at nanoscale greatly depend amount oxygen vacancies present in layer ambient humidity. The photocatalytic effect (PCE) used qualitatively control reversibly switch wettability between hydrophobic superhydrophilic states. Because can attract water molecules, during AFM friction...

We have successfully grown and characterized [Fe/Tb]10/Fe(001)/F57e(001)/MgO(001) multilayer contacts on a GaAs-based light emitting diode. Using F57e conversion-electron Mössbauer spectroscopy at room temperature (RT) 4.2 K, we provide atomistic proof of large perpendicular Fe spin components in zero external field below RT the F57e(001)/MgO(001) interface. Further, indirect evidence interfacial atomic moments is provided. Our serve as prototype aligner for remanent electrical injection RT.

Samarium ions of 200 keV in energy were implanted into highly-resistive molecular-beam-epitaxy grown GaN thin films with a focused-ion-beam implanter at room temperature. The implantation doses range from 1 × 1014 to 1016 cm−2. Structural properties studied by x-ray diffraction and Raman-scattering spectroscopy revealed Sm incorporation matrix without secondary phase. optical measurements showed that the band gap constants changed very slightly implantation. Photoluminescence emission...

This study examines resistive switching in a Cu/ZnO/ITO structure, uncovering an anomalous phenomenon that provides insights into the mechanisms of parallel conducting filaments ZnO thin films. The current–voltage (I–V) characteristics exhibit sharp switch at positive threshold voltage around 2 V, transitioning from high resistance pristine state to low state, interpreted as formation Cu filament via electrochemical metallization. However, after this forming process, device remains and...

Abstract Two different concepts for transferring spin‐optoelectronics to practical room temperature operation devices are explained. First, electrical spin injection in the absence of an external magnetic field and up is demonstrated first time using Fe/Tb‐multilayers as Schottky‐injectors on common LED‐structures. Complete switching polarization from one orientation opposite feasible within ±0.3 T. Second, amplification spin‐information vertical‐cavity surface‐emitting lasers (VCSELs) by...

Ga N ∕ Al x 1 − heterostructures containing a two-dimensional electron gas (2DEG) 27nm underneath the surface were focused-ion-beam implanted with 300keV Gd ions at room temperature. At 4.2K, current-voltage characteristics across rectangles showed that structures remained conducting up to dose of 1×1012cm−2. Extraordinary Hall effect and anisotropic magnetoresistance observed T=4.2K for 3×1011cm−2 Gd. This corresponds 23% reduction in concentration decrease mobility by factor 14 4.2K....