Study On Nonlinear Optical Properties Of Artificial Low-Dimensional Structures

With the emergence and full application of laser technology,the content of nonlinear optics is more abundant,and it has gradually developed into an independent course system,becoming one of the most important and cutting-edge parts of contemporary scientific research.In the past half-century of development,nonlinear optics has made great breakthroughs in principles and material development,and has formed a series of positive results,which have had a huge impact on our production and life,and have played a major role.value.It can be said that in terms of optics,nonlinear optics is a very important part of it.The first chapter of the paper mainly introduces the research background of non-linear optics,the research significance and the research method used in the paper,and describes the knowledge of artificial low-dimensional material quantum dots and quantum wells.It also describes the achievements made in recent years in the research of nonlinear optics in low-dimensional nanomaterials.The second chapter of the thesis studies the light absorption coefficient of asymmetric Gaussian potential quantum dots under the action of electric field.First,the expression of the system Hamiltonian and the corresponding expressions of energy level and wave function are given.After that,the expression of the system light absorption coefficient is given using density matrix and iterative method.The effects of electric field size,asymmetric Gaussian potential parameters,quantum dot size and incident light intensity on the light absorption coefficient are analyzed in detail.The third chapter of the paper studies the change of the optical rectification coefficient of the ring-shaped quantum pseudo-dot system.The optical rectification coefficient of the ring-shaped quantum pseudo-dot system in spherical coordinates is calculated.By solving the Schrodinger equation of the system,the energy level and wave function of the system are obtained,and the expression of the optical rectification coefficient is given by the density matrix and the iterative method.Through calculation,we can find that the system parameter r0,? and the height V0 of the limiting potential can effectively adjust the peak size of the optical rectification coefficient.The fourth chapter of the thesis studies the change of the second harmonic coefficient of the tangent square potential quantum well.By solving the Schrodinger equation of the system,the expressions of the energy level and wave function of the system are obtained.After that,the expression of the second harmonic of the system is given using density matrix and iterative method.The influence of the structure parameters V0 and L of the tangent square potential on the change of the second harmonic coefficient of the system is discussed.The fifth chapter of the thesis studies the influence of oblique magnetic field on the refractive index of anisotropic parabolic quantum dots.The expression of the system Schrodinger equation is given,and the expressions of the system linearity and the third-order refractive index change are obtained by the density matrix and iterative method.The structural parameters of the system ?,the tilt angle of the magnetic field and the influence of the limited frequency change on the refractive index change are discussed.At the end of the thesis,the calculation results of the full text and the conclusions of the research are summarized,and further work is prospected in the future.Figure[24]table[0]reference[81]...