Impact Of High-order Dispersions On The Propagation Of Gaussian Light Pulse In Metamaterial

As the synthetic composite material,metamaterials have special dispersion property.Compared with normal medium,its dielectric constant and permeability are both dispersive.They are made from assemblies of multiple elements fashioned from composite materials such as metals or plastics.The materials are usually arranged in repeating patterns,at scales that are smaller than the wavelengths of the phenomena they influence.The regularly stacked structures in metamaterials may entail stronger chromatic dispersion.Our works show that dispersions of metamaterial are greater than that of conventional glass and discloses(chapter 2.5).So dispersion management is an indispensable element while light propagates in MMs,where dispersive effects accumulate to set limits on both the distance and the bit rate of the data transferring.Recent advances in nanofabrication and breakthroughs in the field of MMs have opened up a new range of possibilities in obtaining optical properties on demand[4-5].The dispersive properties of most MMs rely on the electric and magnetic plasma frequencies,which makes adjustment of electricity and magnetism,management of dispersion become possible.Most of our work is to study the application of metamaterial in communication field and the methods,procedures and major study results are as follow:(1)We deduced the equation of single optic pulse propagating in metamaterial based from the Maxwell’s equations and non-loss Drude model,and compared dispersion of metamaterial with that of four normal glasses,finding that dispersions of metamaterial are greater than that of conventional glass and discloses.(2)We did the simulation of pulse propagating in metamaterial and analyzed how different order dispersion and chirp influence the propagation of pulse,finding:(ⅰ)the second order dispersion of metamaterial leads to much more serious pulse expansion than that of normal medium and the sign of β2 can also influence the position of pulse split that caused by third order dispersion;(ⅱ)Chirp can also aggravates pulse split.(3)We still studied the relation between dispersion and structure parameters,finding:two types of dispersion engineered MMs can exhibit almost mutually reversible group-velocity dispersion(GVD)coefficients,and meanwhile we can find the third order dispersion is so small allowing a reasonably long transmission without pulse splitting though it is usually very strong in MMs and always positive so as not to be compensable.