Basic mechanisms controlling orbital order and orbital fluctuations in transition metal oxides
are discussed. The lattice driven classical orbital picture, eg like in manganites LaMnO 3, is …

Research on the oxide perovskites has uncovered electronic properties that are strikingly
enhanced compared with those in conventional metals. Examples are the high critical …

Bad metals have a large resistivity without being strongly disordered. In many bad metals
the Drude peak moves away from zero frequency as the resistivity becomes large at …

This review shows the great impact of charge ordering upon the magnetic and transport
properties of mixed valent Co4+/Co3+ and Co3+/Co2+ cobalt oxides. The relationships …

Na x CoO 2, the parent compound of the recently synthesized superconductor Na x CoO 2∶
y H 2 O, exhibits bulk antiferromagnetic order below∼ 20 K for 0.75≤ x≤ 0.9. We have …

Temperature-and frequency-dependent infrared spectroscopy identifies two contributions to
the electronic properties of the magnetic kagome metal Fe 3 Sn 2: two-dimensional Dirac …

Temperature-dependent reflectivity studies on the nonmagnetic kagome metal RbV 3 Sb 5
in a broad energy range (50–20000 cm− 1, equivalent to 6 meV–2.5 eV) down to 10 K are …

The crystal and magnetic structures of brownmillerite-like Sr2Co1. 2Ga0. 8O5 with a stable
Co3+ oxidation state at both octahedral and tetrahedral sites are refined using neutron …

We report polarized-and unpolarized-neutron scattering measurements of magnetic
excitations in single-crystal Na 0.75 CoO 2. The data confirm ferromagnetic correlations …

Quantum acoustics—a recently developed framework parallel to quantum optics—
establishes a nonperturbative and coherent treatment of the electron-phonon interaction in …