Related papers: Phonon-assisted optical excitation in the narrow b…
We investigated the temperature-dependent evolution of the electronic structure of the Jeff,1/2 Mott insulator Sr2IrO4 using optical spectroscopy. The optical conductivity spectra $\sigma(\omega)$ of this compound has recently been found to…
We report on the optical excitation spectra in Sr$_2$VO$_4$. The phonon modes are assigned and their evolution with temperature is discussed in the frame of the different phase transitions crossed upon cooling. Besides the expected…
The infrared transmission measurement was performed for a two-dimensional spin-orbit coupling induced Mott insulator Sr$_{2}$IrO$_{4}$ with a layered-perovskite structure. A phonon-assisted magnon mode was observed at around 1870 cm$^{-1}$…
In indirect band gap materials, phonon-assisted processes are key mechanisms for photoluminescence (PL). Using a first-principles many-body approach, we systematically investigate the phonon-assisted PL in bilayer MoS$_2$ and its dependence…
Raman scattering experiments on stoichiometric, Mott-insulating LaTiO$_3$ over a wide range of excitation energies reveal a broad electronic continuum which is featureless in the paramagnetic state, but develops a gap of $\sim 800$…
We have observed the characteristic temperature dependence of the intermolecular phonon spectrum in the organic dimer Mott insulator kappa-(ET)2Cu2(CN)3 exhibiting a dielectric anomaly at 30 K. The anomalous spectral narrowing of the 55…
We report a comprehensive Raman study of the phonon behaviour in PdSe$_2$ in the temperature range of 5 K to 300 K. A remarkable change in the Raman spectrum is observed at 120 K: a significant enhancement of the out-of-plane phonon…
An infrared study of the phonon spectra of ZrW2O8 as a function of temperature which includes the low energy (2-10 meV) region relevant to negative thermal expansion is reported and discussed in the context of specific heat and neutron…
We investigated temperature dependent optical conductivity spectra of La_{7/8}Sr_{1/8}MnO_3. Its phonon bending mode starts to be splitted near a structural phase transition temperature. With further cooling, strength of a mid-infrared…
We investigate experimentally the ultrafast changes in the spectral response of the Mott insulator $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl ($\kappa$-Cl) upon photodoping with intense excitation at 1.6 eV and probing with continuum pulses…
We have investigated the excitation spectra of $j_{eff}$=$\frac{1}{2}$ Mott insulator Na$_2$IrO$_3$. Taking into account a relativistic multiplet structure of Ir ions, we have calculated the optical conductivity $\sigma(\omega)$ and…
Applying newly developed dynamical density matrix renormalization group techniques at zero and finite temperatures to a Hubbard-Holstein model at half-filling, we examine the optical conductivity of a typical one-dimensional Mott insulator…
The infrared reflectance of the transition metal chalcogenide 1T-TaS2 has been measured at temperatures from 30K to 360K over 30-45,000cm^-1 (4meV-5.5eV). The optical conductivity was obtained by Kramers-Kronig analysis. At 360K only modest…
Sn-doped In$_2$O$_3$ or ITO is the most widely used transparent conducting oxide. We use first-principles calculations to investigate the limitations to its transparency due to free-carrier absorption mediated by phonons or charged defects.…
Magnetic properties of Mott-Hubbard insulators are determined by superexchange interactions mediated by the high-spin (HS) and low-spin (LS) intersite d-d charge excitations, which can be associated with the HS- and LS-Hubbard subbands in…
We have measured the intricate temperature dependence of the Co L2,3 x-ray absorption spectra (2p-3d excitations) of CoO. To allow for accurate total electron yield measurements, the material has been grown in thin film form on a metallic…
The isospin-phonon coupling in Sr2IrO4 is investigated by temperature dependent phonon Raman scattering. Anomalous behavior in the frequency of all studied optical phonons is observed below the magnetic transition temperature TN ~240 K. The…
We develop an approximate theory of phonon-induced topological insulation in Dirac materials. In the weak coupling regime, long wavelength phonons may favor topological phases in Dirac insulators with direct and narrow bandgaps. This…
We propose phonon spectroscopy by electric measurements of the low-temperature conductance of coupled-quantum dots, specifically employing dephasing of the quantum electronic transport by the phonons. The setup we consider consists of a…
We investigate ultrafast dynamics from photoinduced reflectivity of Sr2RhO4 by using femtosecond near-infrared pulses. We observe a clear temperature-dependent anomaly in its electronic dynamics which slows down below 160 K. In addition,…