Landau damping in degenerate solid state plasmas

Helicon waves are found useful for studying Landau damping in degenerate plasmas. The damping is analyzed as the phase velocity of the wave is increased from ω/q v_F to ω/q v_F. There is no first-orderlike transition at ω/q = V_F. In the collisionless limit, the damping tends to zero as ω/q → v_F. For finite collision times τ it does not vanish for ω/q > v_F. Nonlocal corrections to the wavelength exhibit a peak at ω/q = V_F, which degenerates into a shoulder for ωτ 100.