A.A. Sirenko

Electronic band structure and optical phonons of BaSnO3 and Ba0.97La0.03SnO3 single crystals: Theory and experiment

Optical properties of insulating BaSnO3 (BSO) and conducting Ba0.97La0.03SnO3 (BLSO) single crystals were studied at room temperature in a wide spectral range between 0.01 and 5.9 eV by means of spectroscopic ellipsometry. The far-infrared spectra of the optical phonons in BSO and BLSO were complemented by polarized Raman scattering measurements in BSO. The electronic band structure and the optical response (dielectric function) were calculated using density functional theory, which allowed for the interpretation of the main spectroscopic features such as optical phonons and electronic interband transitions. To reconcile the observed experimental spectra with the theory, a departure from the ideal perovskite structure on the local scale was proposed for BSO.

Magnons and crystal-field transitions in hexagonal RMnO3 (R = Er, Tm, Yb, Lu) single crystals

Far-infrared optical transmission spectra of the antiferromagnetic resonances, or magnons, and crystal field transitions have been studied in hexagonal REMnO3 (RE = Er, Tm, Yb, Lu) single crystals. The magnon and CF frequencies, their oscillator strengths, and effective g-factors have been measured using external magnetic fields up to 9 T in the temperature range between 1.5 K and 100 K. The magnon frequency increases systematically with a decrease of the RE ion radius. The magnetic ordering of RE ions (RE=Er, Tm, Yb) was observed at low temperatures T<3.5 K and in strong external magnetic fields. The observed effects are analyzed taking into account main magnetic interactions in the system including exchange of the Mn3+ spins with RE3+ paramagnetic moments.

Infrared-active excitations related to Ho 3 + ligand-field splitting at the commensurate-incommensurate magnetic phase transition in HoMn 2 O 5

Linearly polarized spectra of far-infrared (IR) transmission in

Epitaxial checkerboard arrangement of nanorods in ZnMnGaO 4 films studied by x-ray diffraction

{\text{HoMn}}_{2}{\text{O}}_{5}

Far-infrared spectra of the magnetic exchange resonances and optical phonons and their connection to magnetic and dielectric properties of Dy3Fe5O12 garnet

multiferroic single crystals have been studied in the frequency range between 8.5 and

Infrared-active Optical Phonons and Magnetic Excitations in the Hexagonal Manganites RMnO3 (R = Ho, Er, Tm, Yb, and Lu)

105\text{ }{\text{cm}}^{\ensuremath{-}1}

Mueller matrices for anisotropic metamaterials generated using 4 × 4 matrix formalism

and for temperatures between 5 and 300 K. Polarization of IR-active excitations depends on the crystallographic directions in

Far-IR magnetospectroscopy of magnons and electromagnons in TbFeO3 single crystals at low temperatures

{\text{HoMn}}_{2}{\text{O}}_{5}

Ellipsometry studies of the optical phonons in hexagonal manganites

and is sensitive to the magnetic phase transitions. We attribute some of the infrared-active excitations to electric-dipole transitions between ligand-field (LF) split states of

R

{\text{Ho}}^{3+}