Manipulation Of Laplacian Fields Using Metamaterials And Transformation Optics And Its Applications

During the past years,metamaterials and transformation optics have attracted considerable attention due to their magic way for manipulating physical fields and many potential applications.Up to date,metamaterials and transformation optics have been employed to manipulate various waves,including electromagnetic wave,acoustic wave,matter wave,elastic wave and so on.Recently,the concepts of metamaterials and transformation optics have been extended to the manipulation of Laplacion fields like dc current,static magnetic field,thermal flux and mass diffusive field.However,less attention has been focused on electrostatic field,multi-physic fields and Laplacion fields in film system.Here,investigations were conducted as follow:Firstly,the concepts of metamaterials and transformation optics are used to manipulate electrostatic field.As an example,an electrostatic field invisibility cloak which can perfectly hide objects without disturbing external electrostatic fields has been theoretically investigated and experimentally demonstrated,where both cancelling technology and transformation optics(TO)have been employed.The potential devices based on such method have also suggested.Secondly,we propose a general method of constructing bifunctional metamaterials(especially bifunctional electric-thermal metamaterials),for achieving manipulation of multi-physical fields on the basis of our previous achievements.We will first design a bifunctional metamaterial with independently controllable electric conductivity tensor and thermal conductivity tensor based on effective theory,and systematically investigate the effect of geometrical parameters and material parameters on the electric and thermal properties.Thirdly,a bifunctional concentrator capable of concentrating two kinds of fields(electric and thermal fields)to a given region simultaneously and keeping the external fields without distortion is proposed and experimentally demonstrated.To achieve this goal,fan-shaped structure which is composed of alternating wedges is proposed and is further demonstrated to concentrate both electric and thermal fields simulta neously.Furtherly,we pay attention on manipulation of Laplacion fields in film system and propose a general practical method of achieving bifunctional metamaterial applicable for such system based on microfabrication techniques,and then systematically investigate the effect of geometrical parameters and material parameters on the electric and thermal properties.Finally,the manipulation of multi-physics field is proposed through combination of passive and active schemes.In this method,one field is ma nipulated with active scheme while the other with passive scheme.A bifunctional cloak that can function as electric and thermal invisibility cloak is designed and fabricated.Furthermore,another device that can independently and simultaneously manipulate electric and thermal is also demonstrated.