Related papers: Optic phonons and the soft mode in 2H-NbSe2
We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe$_{2}$, that we measure by scanning tunneling spectroscopic imaging. We show from the…
We report results of Raman scattering experiments on twin-free BaFe$_{2}$As$_{2}$ with the main focus placed on understanding the influence of electronic and spin degrees of freedom on the lattice dynamics. In particular, we scrutinize the…
We study theoretically the quenching of a charge-density-wave phase in a model system of a quasi-two dimensional material, which includes both electron-hole and electron-phonon interactions leading, respectively to excitonic and…
We report an inelastic neutron scattering investigation of phonons with energies up to 159 meV in the conventional superconductor YNi$_2$B$_2$C. Using the SWEEP mode, a newly developed time-of-flight technique involving the continuous…
Electron-phonon scatterings in solid-state systems are pivotal processes in determining many key physical quantities such as charge carrier mobilities and thermal conductivities. Here, we report on the direct probing of phonon mode specific…
We report the pressure dependence of the optical response of LaTe$_2$, which is deep in the charge-density-wave (CDW) ground state even at 300 K. The reflectivity spectrum is collected in the mid-infrared spectral range at room temperature…
Charge-density wave order is now understood to be a widespread feature of underdoped cuprate high-temperature superconductors, although its origins remain unclear. While experiments suggest that the charge-ordering wavevector is determined…
Charge density waves (CDWs) involve coupled amplitude and phase degrees of freedom, but direct access to local amplitude correlations remains experimentally challenging. Here, we report cryogenic four-dimensional scanning transmission…
We present a study of the lattice dynamical properties of superconducting SrPt$_3$P ($T_c = 8.4$ K) via high-resolution inelastic x-ray scattering (IXS) and ab initio calculations. Density functional perturbation theory including spin-orbit…
We propose a fully $ \textit{ab initio} $ approach to predicting thermal attenuation in elastic helium atom scattering amplitudes, validated through strong agreement with experiments on Nb(100) and (3$\times$1)-O/Nb(100) surfaces. Our…
Quasi-one-dimensional transition-metal chalcogenide Ta$_2$PdSe$_6$ is a promising thermoelectric semimetal due to the strong electron-hole asymmetry in the carrier lifetime. However, the microscopic origin of such a strong asymmetry remains…
We report on the dynamics of coherent phonons in semimetal 1T'-MoTe2 using femtosecond pump-probe spectroscopy. On an ultrafast sub-picosecond time scale at room temperature, a low frequency and long-lifetime shear phonon mode was observed…
Flat-band (FB) materials have emerged as promising platforms for exploring exotic quantum phases. While numerous candidates have recently been identified through spectroscopic techniques such as angle-resolved photoemission spectroscopy,…
Research on charge-density-wave (CDW) ordered transition-metal dichalcogenides continues to unravel new states of quantum matter correlated to the intertwined lattice and electronic degrees of freedom. Here, we report an inelastic x-ray…
We investigate the temperature dependence of photon coherence properties through two photon interference (TPI) measurements from a single QD under resonant excitation. We show that the loss of indistinguishability is only related to the…
A detailed investigation of BaNi2(As,P)2 single crystals using high-resolution thermal-expansion, heat-capacity,Young-modulus and resistivity measurements is presented. The experimental data are complemented by density-functional…
The origin of charge density wave (CDW) is a long-term open issue. Furthermore, the evolution of phonon-phonon interactions (PPI) across CDW transitions has rarely been investigated. Besides, whether electron-phonon coupling (EPC) would be…
We report inelastic light scattering from underdamped plasmons in azetidinium lead bromide (AzPbBr3). The plasmons are very strongly temperature dependent and serve as a soft mode for the semiconductor-insulator phase transition near TC…
Charge density waves (CDWs) underpin the electronic properties of many complex materials. Near-equilibrium CDW order is linearly coupled to a periodic, atomic-structural distortion, and the dynamics is understood in terms of amplitude and…
Strong electron-electron interactions are known to significantly modify the electron-phonon coupling relative to the predictions of density functional theory, but this effect is challenging to calculate with realistic theories of strongly…