Manipulating Opical Field In Conformal Transformation Optical Structures

The change of information technology has a profound influence on people's work,life and even ideas.At present the information carriers are mainly electronic and photons.With the development of electronic chip technology,Moore's law is facing more and more serious challenges.At the same time,with the explosion of information,people have put forward higher requirements on communication speed and capacity.Considering that the photon can be used as the fastest information carrier,the photonic chip technology has attracted more and more attention.In order to realize the photon integration,various micro-nano photon systems are proposed,such as photonic crystals,surface plasmon polaritons,metamaterials and metasurfaces and so on.On the other hand,in order to break through the existing framework and achieve better photonic integration technology,theorists put forward the design method of transformation optics(TO)based on the basic physics principle.Normally,light travels along a straight line in a flat space-time.However,according to Einstein's general theory of relativity,photons travel along the curve in curved space-time.Similarly,the trajectories of the photons in an inhomogeneous medium are also curved.Based on this similarity,it is proposed to control the propagation of photons in microstructural materials by simulated curved space-time.And all kinds of TO devices have been implemented.Since TO has been put forward,after years of development in both theory and experiment,transformation optics has become an important method to control the propagation of electromagnetic waves and has been widely accepted.In two-dimensional space,conformal transformation optics(CTO),as a branch of TO,has attracted considerable attentions.Because CTO requires inhomogeneous and isotropic materials,it has a certain advantage over the traditional TO materials.Although CTO has many novel theoretical designs,it faces a great challenge in experimental technology.Due to these material processing technology,there are not many works in TO experiment,especially in visible light band.The creative points of this thesis include:Based on the self-assembly technology of polymer film and fluorescence imaging characterization technology,breakthrough have been made in the structure fabrication and experimental measurement technology of CTO,CTO structures are successfully realized in optical band,and several specific functions of CTO devices are demonstrated.The major content of this dissertation can be concluded as follows:1.The Mikaelian lens is obtained in the physical space by CTO,and this device is fabricated by using a gradient-index micro-structured optical waveguide technique in our laboratory.The self-focusing property for geometry optics and Talbot effect for wave optics are demonstrated in experiment.Further research shows that the Talbot effect in such a system has a potential application to transfer digital information without diffraction.2.We achieve effective index potential as analogy of gravity field by CTO.One gaussian beam is transformed to one airy beam in simulated gravity field area,and we observed the reversible beam shaping between Gauss beam and airy beam in the whole sample area.Finally we explained the airy beam in the simulation gravitational field by using the Landau method.3.Starting from well-known absolute instruments for perfect imaging,we design different types of geodesic lens with conformal coordinate transformation.We demonstrate that light rays confined on geodesic lenses are closed trajectories,and for optical waves,the spectrum of geodesic lens is degenerate and equidistant with numerical methods.Moreover,we fabricate two geodesic lenses,the spindle and the spherical surface,in sub-micrometer scale,where curved light rays are closed with high accurate precision.As an extension part,we introduce the research progress and some other experimental results of curved waveguide based on the embedding graph.