64 citations · 203 across the 6 of their papers we have counts for
6 papers
Optical evidence of quantum rotor orbital excitations in orthorhombic manganites
N. N. Kovaleva, K. I. Kugel, Z. Potucek +8
In magnetic compounds with Jahn-Teller (JT) ions (such as Mn3+ or Cu2+), the ordering of the electron or hole orbitals is associated with cooperative lattice distortions. There the…
Anomalous multi-order Raman scattering in LaMnO_3: a signature of a quantum lattice effect in a Jahn-Teller crystal
N. N. Kovaleva, O. E. Kusmartseva, K. I. Kugel +8
The multi-order Raman scattering is studied up to a fourth order for a detwinned LaMnO_3 crystal. Based on a comprehensive data analysis of the polarisation-dependent Raman spectra…
Dipole-active optical phonons in YTiO_3: ellipsometry study and lattice-dynamics calculations
N. N. Kovaleva, A. V. Boris, L. Capogna +6
The anisotropic complex dielectric response was accurately extracted from spectroscopic ellipsometry measurements at phonon frequencies for the three principal crystallographic dir…
Optical response of ferromagnetic YTiO_3 studied by spectral ellipsometry
N. N. Kovaleva, A. V. Boris, P. Yordanov +8
We have studied the temperature dependence of spectroscopic ellipsometry spectra of an electrically insulating, nearly stoichiometric YTiO_3 single crystal with ferromagnetic Curie…
C-axis lattice dynamics in Bi-based cuprate superconductors
N. N. Kovaleva, A. V. Boris, D. Munzar +8
We present results of a systematic study of the c axis lattice dynamics in single layer Bi2Sr2CuO6 (Bi2201), bilayer Bi2Sr2CaCu2O8 (Bi2212) and trilayer Bi2Sr2Ca2Cu3O10 (Bi2223) cu…
Lattice Relaxation and Charge-Transfer Optical Transitions Due to Self-Trapped Holes in Non-Stoichiometric LaMnO Crystal
N. N. Kovaleva, J. L. Gavartin, A. L. Shluger +2
We use the Mott-Littleton approach to evaluate polarisation energies in LaMnO lattice associated with holes localized on both Mn cation and O anion. The full (ele…