We predict a double-resonant feature in the magnetic field dependence of the phonon-mediated longitudinal conductivity σxx of a two-subband quasi-twodimensional electron system in a quantizing magnetic field. The two sharp peaks in σxx appear when the energy separation between two Landau levels belonging to different size-quantization subbands is favorable for acoustic-phonon transitions. One-p...

This work develops a Monte Carlo (MC) simulation method for calculating the heat generation rate in electronic nanostructures. Electrons accelerated by the electric field scatter strongly with optical phonons, yet heat transport in silicon occurs via the faster acoustic modes. The MC method incorporates the appropriate energy transfer rates from electrons to each phonon branch. This accounts fo...

Time dynamics of photoexcited electron-hole pairs is important for a number of technologies, in particular solar cells. We combined ultrafast pump-probe Raman scattering and photoemission to directly follow electron-hole excitations as well as the G-phonon in graphite after an excitation by an intense laser pulse. This phonon is known to couple relatively strongly to electrons. Cross-correlatin...

K(3) picene is a superconducting molecular crystal with a critical temperature of T(c) = 7 or 18 K, depending on the preparation conditions. Using density functional theory we show that electron-phonon interaction accounts for T(c) 3-8 K. The average electron-phonon coupling, calculated by including the phonon energy scale in the electron-phonon scattering, is λ = 0.73 and ω(log) = 18.0 meV. In...

A theory is presented to interpret the phonon drag magneto-thermopower oscillations observed in a periodically modulated two-dimensional electron gas. The thermoelectric and phonon drag tensors are obtained by solving a Boltzmann equation driven by an anisotropic electron-phonon scattering rate reflecting the twofold symmetry of the Fermi surface. It is shown that commensurability oscillations ...

Our experiment shows that the thermal emission of phonon can be controlled by magnetic resonance (MR) mode in a metasurface (MTS). Through changing the structural parameter of metasurface, the MR wavelength can be tuned to the phonon resonance wavelength. This introduces a strong coupling between phonon and MR, which results in an anticrossing phonon-plasmons mode. In the process, we can manipu...

Intense electron-phonon scattering near the peak electric field in a semiconductor device results in nanometer-scale phonon hotspots. Past studies have argued that ballistic phonon transport near such hotspots serves to restrict heat conduction. We reexamine this assertion by developing a new phonon transport model. In a departure from previous studies, we treat isotropic dispersion in all phon...

We survey our recent theoretical studies on the generation and detection of coherent radial breathing mode (RBM) phonons in single-walled carbon nanotubes and coherent radial breathing like mode (RBLM) phonons in graphene nanoribbons. We present a microscopic theory for the electronic states, phonon modes, optical matrix elements and electron-phonon interaction matrix elements that allows us to...

A method for calculating the phonon self-energy in metals arising from the coupling between phonons and electrons near the Fermi surface is developed. The essence of this scheme is the separation of the inter- and intraband parts of the electron polarizability. The intraband contribution provides extra screenings and is closely related to the electron-phonon coupling and phonon softening in met...

The single-layer black phosphorus is characteristic for its puckered structure, which has led to distinct anisotropy in its optical, electronic, and mechanical properties. We use the non-equilibrium Green's function approach and the first-principles method to investigate the thermal conductance for single-layer black phosphorus in the ballistic transport regime, in which the phonon-phonon scatt...