Related papers: Octahedral tilts and electronic correlations in La…
We report an x-ray scattering study of octahedral tilt ordering in the manganite series Pr$_{1-x}$Ca$_x$MnO$_3$ with x=0.4 and 0.25 and in LaMnO$_3$. The sensitivity to tilt ordering is achieved by tuning the incident x-ray energy to the…
We report resonant x-ray scattering data of the orbital and magnetic ordering at low temperatures at the Mn $L_{\rm 2,3}$ edges in \lsmo. The orderings display complex energy features close to the Mn absorption edges. Systematic modeling…
Soft X-ray resonant scattering studies at the Mn $L_{\texttt{II, III}}$- and the La $M_{\texttt{IV, V}}$- edges of single-crystal LaSr$_2$Mn$_2$O$_7$ are reported. At low temperatures, below $T_\texttt{N} \approx 160$ K, energy scans with a…
We have utilized the resonant x-ray diffraction technique at the Mn L-edge in order to directly compare magnetic and orbital correlations in the Mn sub-lattice of Pr0.6Ca0.4MnO3. The resonant line shape is measured below T_OO ~ 240 K at the…
We report the first direct resonant soft x-ray scattering observations of orbital ordering. We have studied the low temperature phase of La$_{0.5}$Sr$_{1.5}$MnO$_4$, a compound that displays charge and orbital ordering. Previous claims of…
We investigate the interplay of the electronic and structural transition in La$_{0.2}$Sr$_{0.8}$MnO$_{3}$. The transport and specific heat measurements exhibit unusual evolutions and signature of a first order phase transition around 265 K.…
We have investigated the low temperature phase of a Nd0.5Sr0.5MnO3 single crystal by x-ray resonant scattering at the Mn K-edge of the (3 0 0), (0 3 0) and (0 5/2 0) reflections. Strong resonances were observed for the s-s' channel in the…
From low-temperature Synchrotron X-ray diffraction, a precise thermal characterization of octahedral distortions in single phase Ruddlesden-Popper Ca3Mn2O7 is performed. Highly sensitive close-steps temperature dependences of Mn-O-Mn bond…
NiO6 octahedral tilts in the LaNiO3/SrTiO3 superlattices are quantified using position averaged convergent beam electron diffraction in scanning transmission electron microscopy. It is shown that maintaining oxygen octahedra connectivity…
A detailed analysis of the crystal structure in RETiO3 with RE = La, Nd, Sm, Gd, and Y reveals an intrinsic coupling between orbital degrees of freedom and the lattice which cannot be fully attributed to the structural deformation arising…
We present the results of a systematic x-ray scattering study of the charge and orbital ordering in the manganite series Pr$_{1-x}$Ca$_x$MnO$_3$ with $x$=0.25, 0.4 and 0.5. The temperature dependence of the scattering at the charge and…
We present a combined study of Ni $K$-edge resonant x-ray scattering and density functional calculations to probe and distinguish electronically driven ordering and lattice distortions in nickelate heterostructures. We demonstrate that due…
The local and intermediate structure of stoichiometric LaMnO$_3$ has been studied in the pseudocubic and rhombohedral phases at high temperatures (300 to 1150 K). Neutron powder diffraction data were collected and a combined Rietveld and…
The local atomic disorder and the electronic structure in the environment of manganese atoms in LaMnO_3 has been studied by x-ray absorption spectroscopy, over a temperature range (300K to 870K) covering the orbital ordering transition…
We model short-period superlattices of WO$_3$ and ReO$_3$ with first-principles calculations. In fully-relaxed superlattices, we observe that octahedral tilts about an axis in the planes of the superlattices do not propagate from one…
We report resonant x-ray scattering studies of charge and orbital order in Pr_{1-x}Ca_{x}MnO_3 with x=0.4 and 0.5. Below the ordering temperature, T_O=245 K, the charge and orbital order intensities follow the same temperature dependence,…
The interactions between $e_g$ orbitals in neighboring sites are investigated in LaMnO$_3$ by taking into account virtual exchange of electrons and phonons. The spin and orbital ordering temperatures and the spin wave dispersion relation…
The perovskite-like compounds ACu3Ru4O12 (A=Na,Ca,Sr,La,Nd) are studied by means of density functional theory based electronic structure calculations using the augmented spherical wave (ASW) method. The electronic properties are strongly…
Charge and orbital ordering behaviors in the half doped bi-layered compound LaSr2Mn2O7 have been studied by resonant and non-resonant X-ray scattering. Three different order parameters, which correspond to the A-type antiferromagnetic, a…
The anharmonic vibrational dynamics in nearly stoichiometric La2CuO4+delta is studied by means of anelastic and ^{139}La NQR relaxation. In the absorption component of the elastic susceptibility as well as in the nuclear relaxation rate a…