Dynamic pair excitations in 2D Fermi fluids

We apply a theory (Böhm et al 2006 AIP Conf. Proc. 850 111, 2007 Int. J. Mod. Phys. B 21 2055) developed recently on dynamic two-pair fluctuations to layered systems, such as electrons in semiconductor hetero-structures or He on graphite. The theory fulfils the zeroth and first frequency moment sum rule. Results are presented for the static effective particle-hole interaction, the dynamic structure function and the dispersion of the plasmon.