The Study On The Manipulation And The Nonlinear Effect Of The Vector Vortex Light Field

With the development of laser technology,in order to fully exploit and utilize the potential of laser,a large number of scientific researchers are devoted to the research of light field regulation.Frequency,phase,amplitude,polarization,and coherence are important parameters required to characterize the distribution of the light field,and also constitute multiple degrees of freedom to achieve beam control,which have attracted the attention of scientific researchers.The optical field manipulation methods,the functional optical element engineering and many other applications fields have become popular research objects.Through a variety of light field manipulation methods,the control of multiple characterization parameters such as light field amplitude,phase,and polarization can be achieved,and a complex vector vortex light field with both phase singularity and polarization singularity can be obtained.Thereby greatly enriching the process of the interaction between light and matter has produced many novel optical effects,further promoting the development of new technologies and expanding the application fields of lasers.The vector vortex light field exhibits different optical characteristics from the scalar light field in many aspects such as beam tight focusing and nonlinearity due to its unique vector characteristics.The general optical research is generally only based on the linear and nonlinear transmission of the scalar light field.Therefore,studying the focus transmission characteristics and nonlinear effects of vector light field has obvious physical significance and application value for further revealing its corresponding new effects and new applications.This paper first introduces the domestic and foreign frontier research on the vector vortex light field control technology and the new focusing characteristics and nonlinear effects brought by the vector characteristics.At the same time,the paper gives the corresponding mathematical representations of the vector vortex light field polarization,amplitude,phase,and angular momentum and other parameters.The proposed Jones matrix method is used to represent the light field adjustment process,which is the next light field adjustment technology and The foundation of relevant characteristics research:1.The theory of near-field shape-preserving manipulation based on unitary matrix transformation is proposed.At the same time,the internal relationship between conic refraction and unitary matrix is established.Through the simple optical design consisting of 4f system and conic refraction,the unitary matrix transformation control of the light field is realized.As a result,a near-field shape-preserving control method,which combines a smooth intensity distribution and a complex polarization and phase structure in a single beam,is obtained.This method has the characteristics of low energy loss,low intensity modulation and high degree of freedom of regulation.2.The effect of each control parameter in the control system on the polarization distribution,phase distribution and angular momentum distribution of the vector vortex light field is studied.The vector vortex beams with polarization covering the whole Poincare sphere,the part of the Poincare sphere and single point on Poincare sphere are generated.Meanwhile,the continuous conversion between different light field distributions are realized.3.The focusing characteristics of the generated Poincare light field are researched and analyzed,which can be changed by changing the control parameters of the control system.The different three-dimensional intensity,phase and polarization distribution of the focal field are obtained.Forther more,the distribution of the axial component of the electric field with the fractional order phase singular point are generated.Subsequently,The continuous variation of the orbital angular momentum of the axial component are realized,which has application prospect in particle manipulation.4.We have researched and analyzed the class ? and class ? second harmonious generation characteristics of the generated Poincare light field.The laws of light field orbital angular momentum,frequency doubling conversion efficiency other characteristics with the control parameters are obtained.The second harmonious generation beam with odd-order and fractional-order orbital angular momentum are generated which breaking the limit of even-order orbital angular momentum of second harmonious generation beam in the traditional frequency doubling process.The study found that the walk-off effect in the second harmonious generation process will cause a change in the phase topology of the second harmonious generation beam.The phase singular point separation occurs in the second harmonious generation beam.