Related papers: Optical spectroscopy study on single crystalline L…

We explore spin dynamics of isotopically purified $^{166}$Er:$^{7}$LiYF$_4$ crystal below 1 Kelvin and at weak magnetic fields $<$0.3 T. Crystals grown in our lab demonstrate record-narrow inhomogeneous optical broadening down to 16~MHz.…

The magnetic properties of the layered oxypnictide LaMnAsO have been revisited using neutron scattering and magnetization measurements. The present measurements identify the N\'{e}el temperature $T_N$ = 360(1) K. Below $T_N$ the critical…

The lattice dynamics of LaFeAsO_{1-x}F_{x} (x=0, 0.1) and PrFeAsO_{1-y} (y~0.1) are investigated using inelastic x-ray scattering and ab-initio calculation. Measurements of powder samples provide an approximation to the phonon DOS, while…

The Fe$_3$O$_4$/Si films are considered to be promising materials for THz spintronic applications due to their high temperature magnetic transition and semiconducting properties. In this article, we present the real part of the dielectric…

We report inelastic x-ray scattering experiments on the lattice dynamics in SmFeAsO and superconducting SmFeAsO$_{0.6}$F$_{0.35}$ single crystals. Particular attention was paid to the dispersions along the [100] direction of three optical…

We report the complex dielectric function of high-quality Na_3Ir_3O_8 single crystals determined by spectroscopic ellipsometry in the spectral range from 15 meV to 2 eV. The far-infrared phonon spectra exhibit highly asymmetric line shapes…

The glasses in the system (100-x)TeO2-xCaCu3Ti4O12, (x=0.25 to 3 mol %) were fabricated. The color varied from olive green to brown as the CaCu3Ti4O12 (CCTO) content increased in TeO2 matrix. The X-ray powder diffraction and differential…

Optical reflection measurements within the highly conducting (a,b)-plane of the organic metal (BEDT-TTF)_4[Ni(dto)_2] reveal the gradual development of a sharp feature at around 200 cm as the temperature is reduced below 150 K. Below this…

In the local or itinerant extreme, magnetic excitations can be described by the Heisenberg model which treats electron spins as localized moments, or by the itinerant-electron model where the exchange interaction between electrons leads to…

We report optical spectroscopic measurements on electron- and hole-doped BaFe2As2. We show that the compounds in the normal state are not simple metals. The optical conductivity spectra contain, in addition to the free carrier response at…

We present results of reflectivity measurements with E parallel to c and E perpendicular to c on NdBa2Cu3Ox (Nd123) single crystals close to full oxygen doping. Along the c-axis the optical conductivity shows a well developed absorption…

We study the optical absorption spectra in a polar ferrimagnet GaFeO_3. We consider the E1, E2 and M1 processes on Fe atoms. It is shown that the magnetoelectric effect on the absorption spectra arises from the E1-M1 interference process…

Sizable single crystals of $BaFe_2As_2$ have been grown with self-flux method. The crystals are plate-like with c-axis perpendicular to the plane. The size can be as large as 3 x 5 x 0.2 $mm^3$. The resistivity anisotropy…

Strained nanowires with varying InAs/InP core-shell thicknesses were grown using Chemical Beam Epitaxy. Microphotoluminescence spectroscopy, performed at low temperature, was then used to study the optical properties of single wires.…

The ferrimagnetic spinel $\mathrm{CoV_2O_4}$ has been a topic of intense recent interest, both as a frustrated insulator with unquenched orbital degeneracy and as a near-itinerant magnet which can be driven metallic with moderate applied…

We present measurements of the optical spectra on Na$_{0.7}$CoO$_2$ single crystals. The optical conductivity shows two broad interband transition peaks at 1.6 eV and 3.2 eV, and a weak midinfrared peak at 0.4 eV. The intraband response of…

We have investigated the origin of the large increase in spin-echo decay rates for the $^{77}$Se nuclear spins at temperatures near to $T=30K$ in the organic superconductor (TMTSF)$_2$ClO$_4$. The measured angular dependence of $T_2^{-1}$…

Effects of X-ray irradiation on the electronic structure of LaAlO$_3$/SrTiO$_3$ (LAO/STO) samples, grown at low oxygen pressure and post-annealed ex-situ till recovery of their stoichiometry, were investigated by soft-X-ray ARPES. The…

Optical reflectivity spectra of La(1-x)Sr(x)MnO(3) (0<=x<=0.30) were measured on cleavage surfaces of single crystals. The optical conductivity $\sigma(w) of ferromagnetic-metal La(0.70)Sr(0.30)MnO(3) is characterized by a Drude-like - but…

The evolution of low-energy spin dynamics in the iron-based superconductor LaFeAsO$_{1-x}$F$_x$ was studied over a broad doping, temperature, and magnetic field range (x = 0 - 0.15, T up to 480K, H up to 30T) by means of As nuclear magnetic…