Related papers: Charge modulations vs. strain waves in resonant x-…
Charge transport in materials has an impact on a wide range of devices based on semiconductor, battery or superconductor technology. Charge transport in sliding Charge Density Waves (CDW) differs from all others in that the atomic lattice…
We report ultrafast x-ray scattering experiments of the quasi-1D charge density wave (CDW) material (TaSe$_4$)$_2$I following photoexcitation with femtosecond infrared laser pulses. From the time-dependent diffraction signal at the CDW…
We report a method for coherent control of $\gamma$-photons, enabling the shaping of $\gamma$-ray intensity in nearly arbitrary waveforms. Different intensity waveforms are created by adjusting the motion profile of a resonant absorber (an…
This paper presents a new method to model X-ray scattering on random rough surfaces. It combines the approaches we presented in two previous papers -- \zs\cite{zhao03} \& \pz\cite{zhao15}. An actual rough surface is (incompletely) described…
X-ray techniques have been used for more than a century to study the atomic and electronic structure in virtually any type of material. The advent of correlated electron systems, in particular complex oxides, brought about new scientific…
We present the results for a model calculation of resonant two-magnon Raman scattering in a spin density wave (SDW) antiferromagnet. The resonant enhancement of the two-magnon intensity is obtained from a microscopic analysis of the…
This paper provides an analysis of radio wave scattering for frequencies ranging from the microwave to the Terahertz band (e.g., 1 GHz - 1 THz), by studying the scattering power reradiated from various types of materials with different…
Charge-density-wave (CDW) order in correlated metals originates in a peaked electronic susceptibility at a finite wavevector $\mathbf Q_0$, set either by Fermi-surface features (nesting or saddle-point singularities) or by momentum-resolved…
The extension of nonlinear spectroscopic techniques into the x-ray domain is in its infancy but holds the promise to provide unique insight into the dynamics of charges in photoexcited processes, which are of fundamental as well as applied…
Previous work on imaging wave packet dynamics with x-ray scattering revealed that the scattering patterns deviate substantially from the notion of instantaneous momentum density of the wave packet. Here we show that scattering patterns can…
We discuss the interplay between electronic correlations and an underlying superlattice structure in determining the period of charge density waves (CDW's), by considering a one-dimensional Hubbard model with a repeated (non-random) pattern…
We performed resonant soft X-ray diffraction on known charge density wave (CDW) compounds, rare earth tri-tellurides. Near the $M_5$ (3d - 4f) absorption edge of rare earth ions, an intense diffraction peak is detected at a wavevector…
Charge density waves (CDWs) are collective electronic states that can reshape and melt, even while confined within a rigid atomic crystal. In two dimensions, melting is predicted to be distinct, proceeding through partially ordered nematic…
We argue that Raman scattering in $B_{1g}$ symmetry allows one to distinguish between phonon-mediated and magnetically-mediated $d-$wave superconductivity. In spin mediated superconductors, $B_{1g}$ Raman intensity develops a resonance at a…
The collective charge density wave (CDW) conduction is modulated by a transverse single-particle current in a transistor-like device. Nonequilibrium conditions in this geometry lead to an exponential reduction of the depinning threshold,…
We report time-resolved x-ray scattering measurements of the transient structural response of the sliding {\bf Q}$_{1}$ charge-density-wave (CDW) in NbSe$_{3}$ to a reversal of the driving electric field. The observed time scale…
We show the ferro-rotational nature of the commensurate charge density wave (CCDW) in $1T$-$\mathrm{TaS}_2$ and track its dynamic modulations by temperature-dependent and time-resolved electric quadrupole rotation anisotropy-second harmonic…
We calculate the X-ray diffraction spectrum produced by a pinned charge density wave (CDW). The signature of the presence of a CDW consists of two satellite peaks, asymmetric as a consequence of disorder. The shape and the intensity of…
The study of elementary bosonic excitations is essential toward a complete description of quantum electronic solids. In this context, resonant inelastic X-ray scattering (RIXS) has recently risen to becoming a versatile probe of electronic…
We demonstrate how the technique of ultrafast resonant x-ray scattering can be applied to imaging dynamics of electronic wave packets in crystals. We study scattering patterns from crystals with electron dynamics in valence bands taking…