Unusual superexchange pathways in a Ni triangular lattice of NiGa$_2$S$_4$ with negative charge-transfer energy

Unusual Symmetries in the Kugel-Khomskii Hamiltonian

Unusual temperature dependence of the oxygen-isotope effect on the exchange-energy of $La_{1-x}Ca_xMnO_3$ at high temperatures

Unusual valence, negative charge-transfer gaps and self-doping in transition-metal compounds

Unusual X-ray excited luminescence spectra of NiO suggestive of a self-trapping of the d-d charge transfer exciton

Unveiling a nematic quantum critical point in multi-orbital systems

Unveiling First Order CMR Transitions in the Two-Orbital Model for Manganites

Unveiling New Magnetic Phases of Undoped and Doped Manganites

Unveiling Order behind Complexity: Coexistence of Ferromagnetism and Bose-Einstein Condensation

Unveiling the nature of three dimensional orbital ordering transitions: the case of $e_g$ and $t_{2g}$ models on the cubic lattice

Unwinding of a one-dimensional topological insulators

Upconversion cooling of Er-doped low-phonon fluorescent solids

Upper bounds on the Witten index for supersymmetric lattice models by discrete Morse theory

Upper critical field of CeCoIn5

Upper Pseudogap Phase: Magnetic Characterizations

Upper-critical dimension in a quantum impurity model: Critical theory of the asymmetric pseudogap Kondo problem

Uranium oxides investigated by X-ray absorption and emission spectroscopies

Using electronic structure changes to map the H-T phase diagram of alpha'-NaV2O5

Using magnetostriction to measure the spin-spin correlation function and magnetoelastic coupling in the quantum magnet NiCl$_2$-4SC(NH$_2$)$_2$

Using the average spectrum method to extract dynamics from quantum Monte Carlo simulations