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We study the anisotropic magnetoresistance and planar Hall effect of La0.8Sr0.2MnO3 when the field is rotated out of the film plane. We fit the data with a model, which consists of two independent contributions related to (a) the orientation of the magnetization relative to the crystal axes and (b) the orientation of the magnetization relative to the current. We find that the first contribution exhibits a two-fold symmetry, which cannot be explained by the angular dependence of the magnetization magnitude, suggesting an intrinsic source which reflects a deviation from cubic symmetry. [ABSTRACT FROM AUTHOR]

We study the anisotropic magnetoresistance and planar Hall effect of La0.8Sr0.2MnO3 when the field is rotated out of the film plane. We fit the data with a model, which consists of two independent contributions related to (a) the orientation of the magnetization relative to the crystal axes and (b) the orientation of the magnetization relative to the current. We find that the first contribution exhibits a two-fold symmetry, which cannot be explained by the angular dependence of the magnetization magnitude, suggesting an intrinsic source which reflects a deviation from cubic symmetry. [ABSTRACT FROM AUTHOR]

Analysis of superconducting ladders consisting of rectangular loops, yields an Ising like expression for the total energy of the ladders as a function of the loops vorticities and the applied magnetic field. This expression shows that fluxoids can be treated as repulsively interacting objects driven towards the ladder center by the applied field. Distinctive repulsive interactions between fluxoids are obtained depending on the ratio l between the loops length and the common width of adjacent loops. A ‘short range’ and a ‘long range’ interactions obtained for l  ≳ 1 and l  ≪ 1, respectively, give rise to remarkably different fluxoid configurations. The different configurations of fluxoids in different types of ladders are illustrated by simulations. [ABSTRACT FROM AUTHOR]

The Hall effect resistivity ?xy of high-quality films of the itinerant ferromagnet SrRuO3 was measured at low temperatures. SrRuO3 films have large uniaxial magnetocrystalline anisotropy, and in the relevant temperature range the easy axis is 30° degrees from the film normal. We measure changes in ?xy associated with changes in the orientation of the magnetization (M) for the same applied magnetic field B [??xy(B,?M)], and we find that with increasing B, ??xy(B,?M) changes its sign and its magnitude becomes more than an order of magnitude larger than the remanent (spontaneous) anomalous Hall effect. Furthermore, it appears that ?xy cannot be described as a sum of a term that depends on B and a term that depends on M, that is, the ordinary Hall effect and the anomalous Hall effect are effectively intermixed. We address qualitatively a possible link between the observed behavior of ?xy and the predicted existence of Weyl nodes in SrRuO3. [ABSTRACT FROM AUTHOR]

We measure the anomalous Hall effect (AHE) in several patterns of the itinerant ferromagnet SrRuO3 before and after the patterns are irradiated with electrons. The irradiation increases the resistivity of the patterns due to the introduction of point defects and we find that the AHE coefficient Rs scales with the total resistivity before and after irradiation which indicates that the AHE is determined by the total resistivity. We discuss possible origins of slight deviations from scaling that are observed at low temperature, particularly below 70 K. [ABSTRACT FROM AUTHOR]

SrRuO3 is an itinerant ferromagnet with a Curie temperature of 150 K and a uniaxial magnetocrystalline anisotropy. Using high-quality epitaxial thin films, we measure at 2 K the anisotropic magnetoresistance and the planar Hall effect as a function of the in-plane current direction and the magnetization orientation. We identify three types of contributions related to (a) the orientation of the magnetization relative to the crystal axes, (b) the direction of the current relative to the crystal axes, and (c) the orientation of the magnetization relative to the current. [ABSTRACT FROM AUTHOR]

We find that the Hall effect resistivity (ρxy) of thin films of La0.8Sr0.2MnO3 varies as a function of the angle θ between the applied magnetic field and the film normal as ρxy = a cosθ + b cos 3θ, where |b| increases with increasing temperature and decreases with increasing magnetic field. We find that the angular dependence of the longitudinal resistivity and the magnetization cannot fully explain the surprising term b, suggesting it is a manifestation of an intrinsic transport property. [ABSTRACT FROM AUTHOR]

We measure the anomalous Hall effect (AHE) resistivity ρxy in thin films of the itinerant ferromagnet SrRuO3. At low temperatures, the AHE coefficient Rs varies with Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed, and at higher temperatures, Rs reaches a peak and then changes sign just below Tc. We find that for all films studied, Rs scales with resistivity in the entire ferromagnetic phase. We attribute the observed behavior to the contribution of the extrinsic side-jumps mechanism and the intrinsic Karplus-Luttinger (Berry phase) mechanism, including the effect of finite scattering rates. [ABSTRACT FROM AUTHOR]

The sheet resistance Rs of Ar+ irradiated SrTiO3 in patterns with a length scale of several microns increases significantly below ~40 K in connection with driving currents exceeding a certain threshold. The initial lower Rs is recovered upon warming with accelerated recovery around 70 and 160 K. Scanning superconducting quantum interference device microscopy shows local irreversible changes in the spatial distribution of the current with a length scale of several microns. We attribute the observed nonuniform enhancement of Rs to the attraction of the charged single-oxygen and dioxygen vacancies by the crystallographic domain boundaries in SrTiO3. The boundaries, which are nearly ferroelectric below 40 K, are polarized by the local electrical field associated with the driven current and the clustered vacancies which suppress conductivity in their vicinity and yield a noticeable enhancement in the device resistance when the current path width is on the order of the boundary extension. The temperatures of accelerated conductivity recovery are associated with the energy barriers for the diffusion of the two types of vacancies. [ABSTRACT FROM AUTHOR]