Propagation Of Full Poincare Beam And It's Applications

Laser is a great invention of the last century humanity,Laser technology is widely used in production and living fields.Laser technology has greatly promoted the progress and development of society.Polarization is an important characteristic of laser.On the basis of a large number of experimental studies,people found that the scintillation index of laser can be reduced effectively by changing the polarization characteristics of laser.This advantage will greatly improve the quality of laser propagation in the atmosphere,and it will be useful in atmospheric laser communication,laser weapon,laser remote sensing and so on.In recent years,researchers have been interested in improving the laser transmission characteristics by changing the polarization characteristics of the laser,The Full Poincare beam is a beam with this kind of special polarization.In classical optics,we use the Stokes parameter to describe the polarization state of light beam.In order to describe the polarization state of light wave more conveniently,H.Poincarépresented a geometric representation of the polarization state of elliptically polarized light.In this method,the sphere is a sphere with a radius of S₀ in the Stokes parameter,which is the Poincare sphere.Each point on the spherical surface corresponds to different polarization states.The polarization state of the cross section of the Poincare beam contains all the states of polarization described by the Poincare sphere.In this paper,we will focus on the study of the theoretical model and the experimental generation of the Poincare beam.Besides,we will study the propagation properties of the Full Poincare beam with different orders in turbulent atmosphere.In chapter 1,we mainly introduce the definition of Full Poincare beam.Besides,we will briefly review the research of full Poincare beam.In chapter 2,it presents basic theory knowledge.First of all,we will introduce the polarization characteristics of laser,mainly related to the definition and characteristics of various polarization states.Besides,we will introduce the description of laser polarization state,mainly related to the polarization of matrix and stork parameter.Finally,we will introduce the basic theory and method of laser propagation.In chapter 3,we will introduce the theoretical basis of the Poincare beam.First of all,we introduce the expressions of the electric field and the expression of the intensity of the full Poincare beam.Then,the polarization states of full Poincare beams with different orders will be introduced.In chapter 4,these beams proposed in chapter 3 have been carried out in the experiment,and our experimental results verify theoretical predictions.Besides,we will study the intensity distribution of full poincare beam after polarizer.Finally,we study the changes of the polarization of the first order Poincare beam against the propagation distanceIn chapter 5,we study the changes of scintillation index when full Poincare beam passing through turbulent atmosphere.In particular,we will reduce the scintillation index of the Poincare beam passing through the turbulent atmosphere by changing the intensity ratio of the LG beam and the Gaussian beam,In chapter 6,the conclusion of this thesis is drawn and some prospects are illustrated.