Nanjing University Basic Principle Dielectric function of free electron gas We have dynamic equation of an electron of plasma sea in an external E field mx+myx=-eE Plasma frequency e x(t)= E() 2 Ne2 m(@2+iyo) (o)=1- +iyo Eomo ne2 P=- E m(o2+iyo) (o)=1- D=61- )E If neglecting the loss @-+iy@ Drude Model o2=o6+K2c2 Dispersion of volume plasmons Dielectric Superlattice Laboratory Nat.Lab.Microstructures Dr.Tao Li taoli@nju.edu.cnNanjing University Dielectric function of free electron gas W h d i ti f l t f l i mm e && & x xE + γ = − We have dynamic equation of an electron of plasma sea in an external E field Plasma frequency 2 2 () () ( ) e t t m i ω γω = + x E 2 2 () 1 Pi ω ε ω ω γω = − + 2 2 0 0 p N em ω ε = 2 2 2 ( ) ne m i ω γω = − + P E 2 2 () 1 P ω γωi ω ε ω ω + = − 2 0 2 (1 ) Pi ω ε ω γω = − + D E Drude Model ω If neglecting the loss 2 2 22 ω ω= +P K c Dispersion of volume plasmons Dielectric Superlattice Laboratory Nat. Lab. Microstructures Dr. Tao Li taoli@nju.edu.cn