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Standing spin waves in a thin film are used as sensitive probes of interface pinning induced by an antiferromagnet through exchange anisotropy. Using coplanar waveguide ferromagnetic resonance, pinning of the lowest energy spin-wave thickness mode in Ni80Fe20/Ir25Mn75 exchange-biased bilayers was studied for a range of Ir25Mn75 thicknesses. We show that pinning of the standing mode can be used to amplify, relative to the fundamental resonance, frequency shifts associated with exchange bias. The shifts provide a unique "fingerprint" of the exchange bias and can be interpreted in terms of an effective ferromagnetic film thickness and ferromagnet-antiferromagnet interface anisotropy. Thermal effects are studied for ultrathin antiferromagnetic Ir25Mn75 thicknesses, and the onset of bias is correlated with changes in the pinning fields. The pinning strength magnitude is found to grow with cooling of the sample, while the effective ferromagnetic film thickness simultaneously decreases. These results suggest that exchange bias involves some deformation of magnetic order in the interface region. [ABSTRACT FROM AUTHOR]

We present low temperature, magnetotransport measurements on a quasi-two-dimensional electron gas created by Ar+-irradiation of SrTiO3. We observe negative (positive) magnetoresistance for fields applied in (out of) the plane of the electron gas. By modulating the mobility μ of the electron gas through an electrostatic field, we find the in-plane magnetoresistance is a function of the cyclotron frequency. The negative in-plane magnetoresistance can be explained by a drop in boundary scattering, which occurs as the cyclotron orbits become smaller than the finite thickness of the electron gas. These results elucidate the critical role boundary scattering plays in the magnetotransport of quasi-two-dimensional electron gases. The implications of these results on recent magnetotransport measurements of LaAlO3/SrTiO3 samples are discussed. [ABSTRACT FROM AUTHOR]

We report a system in which the rotational, vibrational, electronic, and structural properties of condensed molecular H2 can be measured with subnanometer precision using scanning tunneling microscopy. H2 physisorbs around Ni nanoparticles on Au(111) and displays many nonclassical characteristics, including unique disappearance upon heating that is due to changes in the time-averaged phonon ground state population. This collective phenomenon also gives rise to the appearance of submolecular features and constructive overlap at points where neighboring H2 ensembles meet. A model based on the spatial distribution of collective excitations is proposed to explain these properties. [ABSTRACT FROM AUTHOR]

We have studied the anisotropy in the in-plane resistivity and the electronic structure of isovalent Ru-substituted BaFe2As2 in the antiferromagnetic-orthorhombic phase using well-annealed crystals. The anisotropy in the residual resistivity component increases in proportion to the Ru dopant concentration, as in the case of Co-doped compounds. On the other hand, both the residual resistivity and the resistivity anisotropy induced by isovalent Ru substitution are found to be 1 order of magnitude smaller than those induced by heterovalent Co substitution. Combined with angle-resolved photoemission spectroscopy results, which show almost the same anisotropic band structure for both the parent and the Ru-substituted compounds, we confirm the scenario that the anisotropy in the residual resistivity arises from anisotropic impurity scattering in the magnetostructurally ordered phase rather than directly from the anisotropic band structure of that phase. [ABSTRACT FROM AUTHOR]

Using x-ray emission spectroscopy and absorption spectroscopy, it has been possible to directly access the states in the unoccupied conduction bands that are involved with 5f and 6d covalency in oxidized uranium. By varying the oxidizing agent, the degree of 5f covalency can be manipulated and monitored, clearly and irrevocably establishing the importance of 5f covalency in the electronic structure of the key nuclear fuel, uranium dioxide. [ABSTRACT FROM AUTHOR]

We investigate spin transport through polarization-resolved spectroscopy by propagating polariton condensates in a quasi-one-dimensional microcavity ridge along macroscopic distances. Under circularly polarized, continuous-wave, nonresonant excitation, a sinusoidal precession of the spin in real space is observed whose phase depends on the emission energy. The experiments are compared with simulations of the spinor-polariton condensate dynamics based on a generalized Gross-Pitaevskii equation, modified to account for incoherent pumping, decay, and energy relaxation within the condensate. [ABSTRACT FROM AUTHOR]

A correction to the article "Exchange anisotropy pinning of a standing spin-wave mode," which was published in a 2011 issue is presented.