title: Third-frequency-moment sum rule for electronic multilayers
abstract: The authors establish the third-frequency-moment sum rules for the density-density reponse matrix of electronic multilayer structures modeled as an array of N parallel two-dimensional (2D) electron-plasma monolayers. Layer densities and spacings between adjacent layers need not be equal. Contact is made with previously established sum rules for the isolated 2D electron liquid and type-1 infinite superlattices. The case of the equal-density bilayer is considered and its third frequency-moment-sum-rules for the in-phase and out-of-phase inverse dielectric functions are formulated.
authors.affiliation: Department for Intensive Instruction, Nanjing University, Nanjing 210093, People's Republic of China.
authors.initials: D
authors.lastname: Lu
authors.initials: KI
authors.lastname: Golden