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The study of strong electron correlations in transition metal oxides with modern microscopy and diffraction techniques unveiled a fascinating world of nanosize textures in the spin, charge, and crystal structure. Examples range from high $T_c$ superconducting cuprates and nickelates, to hole doped manganites and cobaltites. However, in many cases the appearance of these textures is accompanied with glassiness and multiscale/multiphase effects, which complicate significantly their experimental verification. Here, we demonstrate how nuclear magnetic resonance may be uniquely used to probe nanosize orbital textures in magnetic transition metal oxides. As a convincing example we show for the first time the detection of nanoscale orbital phase separation in the ground state of the ferromagnetic insulator La$_{0.875}$Sr$_{0.125}$MnO$_3$.
The orbital excitations of a series of transition-metal compounds are studied by means of optical spectroscopy. Our aim was to identify signatures of collective orbital excitations by comparison with experimental and theoretical results for predomina
Low-dimensional electron systems, as realized naturally in graphene or created artificially at the interfaces of heterostructures, exhibit a variety of fascinating quantum phenomena with great prospects for future applications. Once electrons are con
We investigate the spectral properties of a hole moving in a two-dimensional Hubbard model for strongly correlated t_2g electrons. Although superexchange interactions are Ising-like, a quasi-one-dimensional coherent hole motion arises due to effectiv
The magnetic properties of the transition metal monoxides MnO and NiO are investigated at equilibrium and under pressure via several advanced first-principles methods coupled with Heisenberg Hamiltonian MonteCarlo. The comparative first-principles an
We discuss the notions of spin-orbital polarization and ordering in paramagnetic materials, and address their consequences in transition metal oxides. Extending the combined density functional and dynamical mean field theory scheme to the case of mat