CHARACTERISING ROOM TEMPERATURE THz METAL SHIELDING USING THE ENGINEERING APPROACH

Abstract

This paper applies the recently introduced electrical engineering approach to investigate room temperature THz metal shielding, using the accurate classical relaxation-efiect frequency dispersion model. It is shown that, with the simplest case of a uniform plane wave at normal incidence to an inflnite single planar shield in air, all flgure of merit parameters for the shield can be accurately characterized. The errors introduced by adopting the traditional and much simpler classical skin-efiect model are also quantifled. In addition, errors resulting from adopting well-established approximations have also been investigated and quantifled. It is shown that the engineering approach allows analytical expressions to be greatly simplifled and predictive equivalent transmission line models to be synthesized, to give a much deeper insight into the behaviour of room temperature THz metal shielding. For example, it is shown that flgures of merit and associated errors (resulting from the use of difierent classical frequency dispersion models) become essentially thickness invariant when the physical thickness of the shield is greater than 3 normal skin depths.