Related papers: Phonon softening and atomic modulations in EuAl$_4…
Charge-density wave (CDW) modulations in underdoped high-temperature cuprate superconductors remain a central puzzle in condensed matter physics. However, despite a substantial experimental verification of this ubiquitous phase in a large…
The selective excitation of coherent phonons provides unique capabilities to control fundamental properties of quantum materials on ultrafast time scales. For instance, in the presence of strong electron-phonon coupling, the electronic band…
While charge density wave (CDW) instabilities are ubiquitous to superconducting cuprates, the different ordering wavevectors in various cuprate families have hampered a unified description of the CDW formation mechanism. Here we investigate…
We use diffuse and inelastic x-ray scattering to study the formation of an incommensurate charge-density-wave (I-CDW) in BaNi$_2$As$_2$, a candidate system for charge-driven electronic nematicity. Intense diffuse scattering is observed…
Charge density wave (CDW) formation in two-dimensional materials is governed by complex competing lattice instabilities that remain incompletely understood. Here, we investigate the structural evolution of monolayer $\mathrm{1T-VSe}_{2}$…
$1T$-TiSe$_2$ is believed to posses a soft electronic mode, i.e., plasmon or exciton, that might be responsible for the exciton condensation and charge-density-wave (CDW) transition. Here, we explore collective electronic excitations in…
A softening of phonon-dispersion has been observed experimentally in under-doped cuprate superconductors at the charge-density wave (CDW) ordering wave vector. Interestingly, the softening occurs below the superconducting (SC) transition…
The charge density wave (CDW) is a macroscopic quantum state characterized by long-range lattice distortion and modulated charge density. Conventionally, CDWs compete with other electronic orders (e.g. superconductivity) and are suppressed…
Low-dimensional materials are susceptible to electronic instabilities such as charge density waves (CDWs), originating from a divergence in the Lindhard electron response function, combined with a finite electron-phonon coupling strength.…
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…
The electron-phonon interaction is a major factor influencing the competition between collective instabilities in correlated-electron materials, but its role in driving high-temperature superconductivity in the cuprates remains poorly…
Soft phonon modes in tetragonal CeCoSi, which undergoes a structural transition at $T_0=12$ K followed by antiferromagnetic order at $T_{\text{N}}=9.5$ K, have been investigated using high-resolution inelastic x-ray scattering. Pronounced…
Atomic rearrangements within crystals lie at the foundation of electron-phonon-coupled phenomena such as metal-insulator transition and superconductivity. Advanced laser-pump-probe studies have recently focused on various…
PbTe crystals have a soft transverse optical phonon mode in the terahertz frequency range, which is known to efficiently decay into heat-carrying acoustic phonons, resulting in anomalously low thermal conductivity. Here, we studied this…
The intermetallic compound BaFe2Al9 exhibits unusual physical properties associated with a charge density wave (CDW) transition. Unlike conventional CDW materials, which typically display subtle structural distortions or lattice…
We report a novel quasi-two dimensional compound of EuTe4 hosting charge density waves (CDW) instability. The compound has a crystallographic structure in a orthorhombic space group Pmmn (No.59) with cell parameters a = 4.6347(2){\AA}, b =…
The superconductor BaNi$_2$As$_2$ exhibits a soft-phonon-driven, incommensurate charge density wave (I-CDW) which is accompanied by a small orthorhombic structural phase transition. Upon further cooling, BaNi$_2$As$_2$ undergoes a…
Topological physics and strong electron-electron correlations in quantum materials are typically studied independently. However, there have been rapid recent developments in quantum materials in which topological phase transitions emerge…
Recently, a first-order phase transition associated with charge density wave (CDW) has been observed at low temperatures in intermetallic compound BaFe$_2$Al$_9$. However, this transition is absent in its isostructural sister compound…
Electron-correlation-driven phonon soft modes have been recently reported in the antiferromagnetic kagome FeGe compound and associated with the observed charge density wave (CDW). In this paper, we present a systematic investigation of the…