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A major question in Fe-based superconductors remains the structure of the pairing, in particular whether it is of unconventional nature. The electronic structure near a vortex can serve as a platform for phase-sensitive measurements to answer this question. By solving the Bogoliubov-de Gennes equations for LiFeAs, we calculate the energy-dependent local electronic structure near a vortex for different nodeless gap-structure possibilities. At low energies, the local density of states (LDOS) around a vortex is determined by the normalstate electronic structure. At energies closer to the gap value, however, the LDOS can distinguish an anisotropic s-wave gap from a conventional isotropic s-wave gap.We show within our self-consistent calculation that in addition, the local gap profile differs between a conventional and an unconventional pairing.We explain this through admixing of a secondary order parameter within Ginzburg-Landau theory. In-field scanning tunneling spectroscopy near a vortex can therefore be used as a real-space probe of the gap structure. [ABSTRACT FROM AUTHOR]

Rashba spin-orbit coupling together with electron correlations in the metallic interface between SrTiO3 and LaAlO3 can lead to an unusual combination of magnetic and orbital ordering. We consider such phenomena in the context of the recent observation of anisotropic magnetism. Firstly, we show that Rashba spin-orbit coupling can account for the observed magnetic anisotropy, assuming a correlation driven (Stoner type) instability toward ferromagnetism. Secondly, we investigate nematicity in the form of an orbital imbalance between dxz/dyz orbitals. We find an enhanced susceptibility toward nematicity due to the van Hove singularity in the low-electron-density regime. In addition, the coupling between in-plane magnetization anisotropy and nematic order provides an effective symmetry breaking field in the magnetic phase. We estimate this coupling to be substantial in the low-electron-density regime. The resulting orbital ordering can affect magneto transport. [ABSTRACT FROM AUTHOR]