Quantized electrons and holes in tellurium surfaces

A calculation has been made for surface phonons at the (001) surface of some fcc and bcc transition metals. A model consisting of first and second neighbor central interactions together with angle bending forces is used. The general harmonic approximation is used. A least mean square fit of the bulk phonon spectrum determines the parameters characterizing the interactions. Specific results have been obtained for surface phonons of Pt, Pd, Cu and Ag as well as Fe and W. The effect of varying the force constant near the surface is also reported showing the possibility for the existence of soft surface modes which may account for superstructures.     

Energy relaxation of warm electrons in (100)-Si-MOSFETs under substrate bias

We have studied the energy loss of warm electrons in a two- dimensional electron gas at the SiSiO₂ interface of (100)-Si- MOSFETs. The application of a negative substrate bias decreases the inelastic electron-phonon interaction considerably at T₁ = 1.8 K. The temperature dependence of the energy loss suggests that at zero substrate bias and low temperatures deformation potential scattering by Si-bulk phonons cannot entirely account for the experimental findings.