ELECTROSTATIC RESPONSE OF A LAYERED SYSTEM OF ELECTRONS - AN APPLICATION TO YBACU3O7-DELTA-

A most general response function of a system consisting of a series of equallly spaced electron layers is formulated in a unified way and th e results are applied to a YBa2Cu3O7-delta. The effective potential, i nduced electron density, dielectric constant, and inverse screening le ngth for an electron on each layer are evaluated and analyzed in terms of various structural parameters of the system. The strength of the d ielectric screening of the layered system of electrons is found, in ge neral, to be intermediate in between those of a purly two-dimensional electron gas and the bulk. And a fixed charged impurity inserted into the YBa2Cu3O7-delta is screened almost completely within a few near-ly ing CuO2 planes.