Related papers: Resonant electron-lattice cooling in graphene
We report the ultrafast dynamics of the 47.4 THz coherent phonons of graphite interacting with a photoinduced non-equilibrium electron-hole plasma. Unlike conventional materials, upon photoexcitation the phonon frequency of graphite…
The impact of lattice type, period, porosity and thickness of two-dimensional silicon phononic crystals on the reduction of thermal conductance by coherent modification of phonon dispersion is investigated using the theory of elasticity and…
We report a comprehensive study of the tuning with electric fields of the resonant magneto-exciton optical phonon coupling in gated graphene. For magnetic fields around $B \sim 25$ T which correspond to the range of the fundamental…
Umklapp processes play a fundamental role as the only intrinsic mechanism that allows electrons to transfer momentum to the crystal lattice and, therefore, provide a finite electrical resistance in pure metals. However, umklapp scattering…
Femtosecond laser excitation of solid-state systems creates non-equilibrium hot electrons that cool down by transferring their energy to other degrees of freedom and ultimately to lattice vibrations of the solid. By combining ab initio…
Quantised sound waves -- phonons -- govern the elastic response of crystalline materials, and also play an integral part in determining their thermodynamic properties and electrical response (e.g., by binding electrons into superconducting…
Electron and phonon transient temperatures are analyzed in the case of nondegenerate semiconductors. An analytical solution is obtained for rectangular laser pulse absorption. It is shown that thermal diffusion is the main energy relaxation…
Tailoring the properties of correlated oxides is accomplished by chemical doping, pressure, temperature or magnetic field. Photoexcitation is a valid alternative to reach out-of-equilibrium states otherwise inaccessible. Here, we…
Materials exhibit various wave-like excitations, among which phonons (lattice vibrations) and magnons (oscillations in ferromagnetic ordering) hold significant promise for future nanoscale technologies. Exploring the interaction between…
In this work we present the results of an inelastic x-ray scattering experiment detailing the behavior of the transverse acoustic [110] phonon in BaFe2As2 as a function of temperature. When cooling through the structural transition…
In graphene moir\'e superlattices, electronic interactions between layers are mostly hidden as band structures get crowded because of folding, making their interpretation cumbersome. Here, the evolution of the electronic band structure as a…
Creating non-equilibrium states of matter with highly unequal electron and lattice temperatures allows unsurpassed insight into the dynamic coupling between electrons and ions through time-resolved energy relaxation measurements. Recent…
Strain engineering has been extended recently to the ultrafast timescales, driving metal-insulator phase transitions and the propagation of ultrasonic demagnetization fronts. However, the non-linear lattice dynamics underpinning interfacial…
We study hot-electron cooling by acoustic and optical phonons in monolayer MoS$_2$. The cooling power $P$ ($P_e = P/n$) is investigated as a function of electron temperature $T_e$ (0-500 $\mathrm{K}$) and carrier density $n$…
Understanding the mechanisms of thermal conduction in graphene is a long-lasting research topic, due to its high thermal conductivity. Peierls-Boltzmann transport equation (PBTE) based studies have revealed many unique phonon transport…
Single-layer graphene is so flexible that its flexural mode (also called the ZA mode, bending mode, or out-of-plane transverse acoustic mode) is important for its thermal and mechanical properties. Accordingly, this review focuses on…
In graphene, after the electric field is turned-on, the ballistic acceleration of charge carriers up to the monochromatic optic phonon energy generates a back-and-forth motion of the whole distribution function between the zero point energy…
In the emergent field of quantum technology, the ability to manage heat at the nanoscale and in cryogenic conditions is crucial for enhancing device performance in terms of noise, coherence, and sensitivity. Here, we demonstrate the active…
We combine femtosecond electron diffuse scattering experiments and first-principles calculations of the coupled electron-phonon dynamics to provide a detailed momentum-resolved picture of the ultrafast lattice thermalization in a thin film…
Because electrons and ions form a coupled system, it is a priori clear that the dynamics of the lattice should reflect symmetry breaking within the electronic degrees of freedom. This has been recently clearly evidenced for the case of…