Abstract
The equation of motion method is used to study the high-frequency conductivity of a single-component plasma in which carriers have a nonquadratic energy-momentum relation. In such a medium current is not conserved in electron-electron collisions, and there are important correlation corrections to the conductivity. The expression for the correction involves the perturbed correlation function in the plasma, and explicitly shows that the correction vanishes in the case of a quadratic energy-momentum relation. Evaluation of the correlation function is only possible if the electron-electron interaction is weak. An approximate calculation is made in this limit, which yields a formula for the conductivity that is correct to second order in the electron-electron interaction.