Investigation of k = 0 phonons in Bi, Cd, Mg, and Zn by Raman scattering

Abstract

Abstract Measurements are reported for optical phonons ( k = 0) by Raman scattering at 300, 80, and 2 K for Bi, Cd, Mg, and Zn. The linewidths are found to increase, and the frequencies to decrease, as the temperature is raised. The temperature dependent portion of the linewidth is attributed to a two‐phonon decay process. In addition, the contributions to the line‐width from the isotope effect, the electron‐phonon interaction, and strains are discussed.