In situ polarized 3He system for the Magnetism Reflectometer at the Spallation Neutron Source Related Articles In situ polarized 3 He system for the Magnetism Reflectometer at the Spallation Neutron Source

Novel mono-static arrangement of the ASDEX Upgrade high field side reflectometers compatible with electron cyclotron resonance heating stray radiation Rev. Sci. Instrum. 83, 10E317 (2012) Density profile measurements with X-mode lower cut-off reflectometry in ASDEX Upgrade Rev. Sci. Instrum. 83, 10E315 (2012) First results of the SOL reflectometer on Alcator C-Mod Rev. Sci. Instrum. 83, 10E309 (2012) Metamaterial near-field sensor for deep-subwavelength thickness measurements and sensitive refractometry in the terahertz frequency range Appl. Phys. Lett. 100, 221101 (2012) High-pressure cell for neutron reflectometry of supercritical and subcritical fluids at solid interfaces Rev. Sci. Instrum. 83, 045108 (2012) Additional information on Rev. Sci. Instrum. We report on the in situ polarized 3 He neutron polarization analyzer developed for the time-of-flight Magnetism Reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. Using the spin exchange optical pumping method, we achieved a 3 He polarization of 76% ± 1% and maintained it for the entire three-day duration of the test experiment. Based on transmission measurements with unpolarized neutrons, we show that the average analyzing efficiency of the 3 He system is 98% for the neutron wavelength band of 2-5 Å. Using a highly polarized incident neutron beam produced by a supermirror bender polarizer, we obtained a flipping ratio of >100 with a transmission of 25% for polarized neutrons, averaged over the wavelength band of 2-5 Å. After the cell was depolarized for transmission measurements, it was reproducibly polarized and this performance was maintained for three weeks. A high quality polarization analysis experiment was performed on a reference sample of Fe/Cr multilayer with strong spin-flip off-specular scattering. Using a combination of the position sensitive detector, time-of-flight method, and the excellent parameters of the 3 He cell, the polarization analysis of the two-dimensional maps of reflected, refracted, and off-specular scattered intensity above and below the horizon were obtained, simultaneously. [http://d

Interrelation between Structure - Magnetic Properties in La0.5Sr0.5CoO3

Differing anisotropic strain induced from the underlying substrates not only control the long-range structural symmetries in La0.5Sr0.5CoO3 but also impact the magnetic properties of these epitaxial thin films. The two dominant structural distortions: oxygen octahedral tilts and epitaxial strain, however, have complex and non-intuitive effects on the splitting of the t2g states and consequently on magnetization

Interrelation between Structure - Magnetic Properties in La0.5Sr0.5CoO3

Differing anisotropic strain induced from the underlying substrates not only control the long-range structural symmetries in La0.5Sr0.5CoO3 but also impact the magnetic properties of these epitaxial thin films. The two dominant structural distortions: oxygen octahedral tilts and epitaxial strain, however, have complex and non-intuitive effects on the splitting of the t2g states and consequently on magnetization

Thickness-dependent crossover from charge- to strain-mediated magnetoelectric coupling in ferromagnetic/piezoelectric oxide heterostructures.

Magnetoelectric oxide heterostructures are proposed active layers for spintronic memory and logic devices, where information is conveyed through spin transport in the solid state. Incomplete theories of the coupling between local strain, charge, and magnetic order have limited their deployment into new information and communication technologies. In this study, we report direct, local measurements of strain- and charge-mediated magnetization changes in the La0.7Sr0.3MnO3/PbZr0.2Ti0.8O3 system using spatially resolved characterization techniques in both real and reciprocal space. Polarized neutron reflectometry reveals a graded magnetization that results from both local structural distortions and interfacial screening of bound surface charge from the adjacent ferroelectric. Density functional theory calculations support the experimental observation that strain locally suppresses the magnetization through a change in the Mn-eg orbital polarization. We suggest that this local coupling and magnetization suppression may be tuned by controlling the manganite and ferroelectric layer thicknesses, with direct implications for device applications