Related papers: Ultrafast charge-transfer dynamics in Ca$_2$CuO$_2…

We report our study on unconventional charge density waves (UCDW) (i.e. a charge density wave with wavevector dependent gap) in pure quasi-one dimensional conductors. We develop a new possible mechanism of establishment of such a low…

We use coherent pump-probe spectroscopy to measure the photoinduced reflectivity \DeltaR, and complex dielectric function, {\delta}\in, of the electron-doped cuprate superconductor Nd_{2-x}Ce_xCuO_{4+\delta} at a value of x near optimal…

Point defects in crystalline materials often occur in multiple charge states. Although many experimental methods to study and explore point defects are available, techniques to explore the non-equilibrium dynamics of the charge states of…

We have measured the far infrared reflectance of the heavy fermion compound URu$_2$Si$_2$ through the phase transition at T$_{HO}$=17.5 K dubbed 'hidden order' with light polarized along both the a- and c-axes of the tetragonal structure.…

The dynamic charge susceptibility and the optical conductivity are calculated in the planar t-J model within the memory function method, working directly in terms of Hubbard operators. The density fluctuation spectrum consists of a damped…

The electron-boson spectral density function I^2ChiOmega responsible for carrier scattering of the high temperature superconductor HgBa2CuO4 (Tc = 90 K) is calculated from new data on the optical scattering rate. A maximum entropy technique…

The formation of bound electron-hole pairs, also called charge-transfer (CT) states, in organic-based photovoltaic devices is one of the dominant loss mechanisms hindering performance. While CT state dynamics following electron transfer…

We report optical reflectivity study on Nd$_{2-x}$Ce$_x$CuO$_4$ over a broad doping range 0$\leq x\leq$0.20. The study reveals a systematic shift of chemical potential with doping. A pronounced peak structure specific to the electron-doped…

Charge-density wave (CDW) is one of the most fundamental quantum phenomena in solids. Different from ordinary metals in which only single particle excitations exist, CDW also has collective excitations and can carry electric current in a…

We study how the color and polarization of ultrashort pulses of visible light can be used to control the demagnetization processes of the antiferromagnetic insulator Cr$_2$O$_3$. We utilize time-resolved second harmonic generation (SHG) to…

Here we report on the dynamics of the structural order parameter in a chromium film using synchrotron radiation in response to photo-induced ultra-fast excitations. Following transient optical excitations the effective lattice temperature…

Transition metal dichalcogenides (TMDCs) have demonstrated significant potential as versatile quantum materials for light absorption and emission. Their unique properties are primarily governed by exciton-photon interactions, which can be…

Transition charge density (TCD) for $ 0^+\to 2_1^+ $ excitation have been calculated for $\rm ^{70,72,74,76}Ge$ nuclei within microscopic variational framework employing $2p_{3/2}, 1f_{5/2}, 2p_{1/2}$ and $1g_{9/2}$ valence space. The…

Signatures of photo-induced superconductivity have been reported in cuprate materials subjected to a coherent phonon drive. A 'cold' superfluid was extracted from the transient Terahertz conductivity and was seen to coexist with 'hot'…

The optical conductivity of the one-band Hubbard model is calculated using the 'Dynamical Cluster Approximation' implementation of dynamical mean field theory for parameters appropriate to high temperature copper-oxide superconductors. The…

Far-infrared reflectance of a MgB2 film has been measured by Fourier-transform spectroscopy for frequencies 10 cm^{-1}<\nu <4000 cm^{-1} above and below the superconducting transition. The data provide clear experimental evidence for the…

Charge density wave (CDW) instability is often found in phase diagrams of superconductors such as cuprates and certain transition-metal dichalcogenides. This proximity to superconductivity triggers the question on whether CDW instability is…

Under varying growth and device processing conditions, ultrabroadband photoconduction (UBPC) reveals strongly evolving trends in the defect density of states (DoS) for amorphous oxide semiconductor thin-film transistors (TFTs). Spanning the…

Photoconductive devices based on ultra-wide-bandgap (UWBG) materials offer a promising pathway toward compact, high-voltage (HV) optoelectronic and optical sensing in harsh environments. In this Letter, we report field-tunable nonlinear…

We report a Cu $K$-edge resonant inelastic x-ray scattering (RIXS) study of charge-transfer excitations in the 2-8 eV range in the structurally simple compound HgBa$_2$CuO$_{4+\delta}$ at optimal doping ($T_{\rm c} = 96.5 $ K). The spectra…