We present a complete dynamic theory for the electron gas at high to metallic densities. The theory combines the dominant features of the shielded-interaction approximation and the T-matrix approximation within a formalism which ensures that the conservation sum rules are exactly satisfied. The theory is shown to be valid for large and small momentum transfers at high to metallic electron densities. It is argued that because conservation laws are maintained, the theory contains valid information about intermediate momentum transfers also. It is found that dynamic properties of the resulting polarization function and the dynamic structure factor cannot be adequately approximated by the well-known local-field construction, and consequently nonlocal effects are important for dynamic properties of the electron gas.
Conserving dynamic theory for the electron gas
NEILSON, DAVID;
1985-01-01
Abstract
We present a complete dynamic theory for the electron gas at high to metallic densities. The theory combines the dominant features of the shielded-interaction approximation and the T-matrix approximation within a formalism which ensures that the conservation sum rules are exactly satisfied. The theory is shown to be valid for large and small momentum transfers at high to metallic electron densities. It is argued that because conservation laws are maintained, the theory contains valid information about intermediate momentum transfers also. It is found that dynamic properties of the resulting polarization function and the dynamic structure factor cannot be adequately approximated by the well-known local-field construction, and consequently nonlocal effects are important for dynamic properties of the electron gas.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.