Influence Of The Shape Of Quantum Dots On The Nonlinear Optical Properties

In the past decade,considerable researches have been delicated to the study of nonlinear optical properties in nanostructures because of its great value in biological medicine,quantum computation and quantum communication etc..Recently,with the development of nanofabrication technique,it makes a breakthrough to fabricate the low-dimension semiconductor material,such as quantum wire,well and dot.The quantum confinement effect in quantum dot is much stronger than in others which reflects the strengthening of the nonlinear optical effects.And the nonlinear optical effects are different in different shapes of quantum dots.For above reasons,we will study the influence of the shape of quantum dots on the nonlinear optical propertiesWith the effective mass approximation,the energy spectrum and wave functions in the system of elliptic and triangular quantum dots(QDs)are calculated by taking advantage of the perturbation method.We also calculated and analyzed the third-harmonic generations(THG)in elliptic and triangular quantum dots with the help of the compact density-matrix approach.Moreover,we have researched the shape effect on the second order nonlinear optical properties in triangular quantum dots with applied electric field.Our results show that the shape of quantum dots has a significant influence on the thirdharmonic generations.Particularly,under the interference of the electric field,the magnitude of external electric field and the shape of TQDs make a big difference on the second-harmonic generations(SHG)coefficient and the optical rectification(OR)coefficient.