(a) Schematic view of the bicrystal boundary (GB) in manganite thin film (2) deposited on bicrystal substrate (1). The crystallographic directions of bicrystal configuration for two parts of the (001) LSMO film are indicated by arrows. The misorientation angles for RB and TB boundary are marked by 2θ′ and 2θ, respectively. Angles and the direction of magnetic field H are determined by the polar angle α and the azimuthal angle β. Axis x corresponds to current flow direction and y is along the bicrystal boundary. (b) A photo of a bicrystal junction connected with logoperiodic antenna.
X-ray diffraction patterns (measured in the 2θ/ω scan mode, log scale on intensity) of the LSMO films deposited onto LAO, NGO, and STO substrates. The dashed line indicates the position of the hypothetical reflection for bulk (002) LSMO. 14 Inset: the dependence of interplane distance of LSMO films a ⊥ (triangular) on a s is shown. Solid line is the dependence of a ⊥ = a s, which is true for unstrained cubic lattice.
Angular dependences of the FMR field H0 for (001) LSMO film in LSMO/LSAT, LSMO/NGO, and LSMO/STO measured at frequency of 9.61 GHz and T = 300 K. Here, symbols are experimental data and solid lines are the calculation using Eq. (1) .
The dependence of uniaxial anisotropy constant on the tilt angle of the (110)NGO substrate plane: open circles are FMR data at a frequency of 9.61 GHz and triangular are microwave absorption data at a frequency of290.6 MHz. Dashed line connects small solid circles calculated using Eqs. (4) and (5) with the parameters taken from Table II .
The angular dependence of FMR resonance magnetic field for two lines observed in LSMO RB-boundary with misorientation angle 2θ′ = 90° at T = 300 K. Easy axis orientation for one part of bicrystal film corresponds to angles φ ≈ 60°/240° (circles) and φ ≈ 150°/330° for other part (squares). The DC magnetic field is along of RB-boundary at φ = 90°.
Magnetic field dependence of the absorption signals at 290.6 MHz for the RB-boundary with misorientation angle of 2θ′ = 90° for different values of the angle α between the external magnetic field and the axis x, T = 300 K. The angular dependence of the absorption maximum (amplitude of the resonance signal) close the angle α = 144° is shown in the inset.
Temperature dependence of the resistances for LSMO RB-junction (2θ′ = 90°) (solid line) and LCMO (2θ = 28°) TB-junction (dashed line). The measurements were carried out at zero external field.
Magnetoresistance of LSMO TB-junction with misorientation angle 2θ = 38° normalized on the resistance at H = 750 Oe (R H) taken at four temperatures. Two curves for fixed temperature correspond to increasing and decreasing magnetic field. Magnetic field direction is determined by the angles α = 45°, β = 90° (see Fig. 1 ).
Temperature dependence of the magnetoresistance MR′ (filled squares) for LSMO TB-junction. The dashed line represents the calculated temperature dependence of MR′ by Eqs. (8) and (10) . The dependence of MR on temperature for the same junction (2θ = 38°) is given in the inset.
DC voltage dependence of the conductance G (V) of LSMO RB-junction (2θ = 38°) at temperatures T = 4 K, 18 K, 64 K, and 128 K. The lines show the fits of the experimental curves by different power functions.
Lattice constant and rocking curve widths for LSMO films deposited on NGO substrate with varying miscut from the (110) plane.
Parameters of magnetic anisotropy for LSMO films deposited on NGO substrate with varying miscut from the (110) plane.
Magnetic anisotropy of LSMO bicrystal junctions for T = 300 K.
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