相关论文: Phonon and exciton temperature-dependent propertie…
Probing phonons, quasi-particle excitations and their coupling has enriched our understanding of these 2D materials and proved to be crucial for developing their potential applications. Here, we report comprehensive temperature, 4-330 K,…
The temperature evolution of the resonant Raman scattering from high-quality bilayer 2H-MoS$_{2}$ encapsulated in hexagonal BN flakes is presented. The observed resonant Raman scattering spectrum as initiated by the laser energy of 1.96 eV,…
Resonance Raman scattering, a very effective and sensitive technique for atomically thin semiconducting transition metal dichalcogenide, can be used to observe the phonons from the entire Brillouin zone. In addition to the significance of…
Temperature influences the performance of two-dimensional materials in optoelectronic devices. Indeed, the optical characterization of these materials is usually realized at room temperature. Nevertheless most {\it ab-initio} studies are…
The band structure of bilayer graphene is tunable by introducing a relative twist angle between the two layers, unlocking exotic phases, such as superconductor and Mott insulator, and providing a fertile ground for new physics. At…
We report Raman spectra measurements on a MoS2 monolayer supported on SiO2 as a function of temperature. Unlike in previous studies, the positions of the two main Raman modes, E2g1 and A1g exhibited nonlinear temperature dependence.…
We develop a theoretical framework for probing moir\'e phonon modes using Raman spectroscopy, and illustrate it with the example of twisted bilayer graphene (TBG). These moir\'e phonons arise from interlayer sliding motion in twisted 2D…
Twisted van der Waals heterostructures unravel a new platform to study strongly correlated quantum phases. The interlayer coupling in these heterostructures is sensitive to twist angles ($\theta$) and key to controllably tune several exotic…
We review vibrational and electronic properties of single and a few layer MoS$_2$ relevant to understand their resonant and non-resonant Raman scattering results. In particular, the optical modes and low frequency shear and layer breathing…
We present a combined experimental and computational study of two-dimensional molybdenum disulfde (MoS2) and the effect of temperature on the frequency shifts of the Raman-active E2g and A1g modes in the monolayer. While both peaks show an…
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…
We theoretically investigated phonon dispersion in AA-stacked, AB-stacked and twisted bilayer graphene with various rotation angles. The calculations were performed using the Born-von-Karman model for the intra-layer atomic interactions and…
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…
Twisted 2D materials exhibit unique vibrational modes called moir\'e phonons, which arise from the moir\'e superlattice. Here, we demonstrate atom-by-atom imaging of phasons, an ultrasoft class of moir\'e phonons in twisted bilayer WSe2.…
We have studied electron scattering by out-of-plane (flexural) phonons in doped suspended bilayer graphene. We have found the bilayer membrane to follow the qualitative behavior of the monolayer cousin. In the bilayer, different electronic…
We report on the temperature dependence of in-plane E2g and out of plane A1g Raman modes in high quality few layers MoS2 (FLMS) prepared using a high temperature vapor-phase method. The materials obtained were investigated using…
Newly measured optical absorption and photoluminescence spectra reveal substantial frequency shifts of both exciton and trion peaks as monolayer MoS2 is cooled from 363 K to 4 K. First-principles simulations using the GW-Bethe-Salpeter…
Twisted bilayer (t-BL) transition metal dichalcogenides (TMDCs) attracted considerable attention in recent years due to their distinctive electronic properties, which arise due to the moire superlattices that lead to the emergence of flat…
We present a Raman scattering study of Ca$_2$RuO$_4$, in which we investigate the temperature-dependence of the lattice dynamics and the electron-phonon interaction below the metal-insulator transition temperature ({\it T}$_{\rm MI}$).…
Two-dimensional layered materials offer the possibility to create artificial vertically stacked structures possessing an additional degree of freedom - $the$ $interlayer$ $twist$. We present a comprehensive optical study of artificially…