Response Functions Approach to Electron Correlations.

Francis S.M. Tsui, Karl F. Freed

Lauri J. Lantto, Pekka Pietiläinen, A. Kallio

The dielectric response of strongly correlated electron gas is studied by using a Jastrow variational many-body wave function to describe the electron-electron correlations in the fluid as well as its static response to a weak external perturbation. The Fermi hypernetted-chain method is employed to obtain an approximation to the local-field correction at a range of metallic densities. Results agree well with those obtained through recent developments of more conventional dielectric formulation.

U. Fano

John C. Kimball

The behavior of interacting electrons is dominated by the Coulomb repulsion in the limit of zero interparticle separation. Hence, in this limit the derivative of the two-particle correlation function is equal to the two-particle correlation function itself divided by the Bohr radius. Because correlation functions can be obtained from linear-response functions, the relation between the correlation function and its derivative can be used as a criterion for the validity of approximate linear-response functions. Some of the more familiar dielectric functions and spin susceptibilities are discussed in this context. For these response functions it is shown that the electric and magnetic response should approach the same ($q\ensuremath{\rightarrow}\ensuremath{\infty}$) asymptotic limit.