压电椭圆柱形InAs/InP核/壳量子点中杂质态线性和非线性光学性质  

Linear and Nonlinear Optical Properties of Impurity States in Piezoelectric Elliptic Cylindrical InAs/InP Core/Shell Quantum Dots

作　　者：韩立志 石磊[1] HAN Lizhi;SHI Lei(College of Science,Inner Mongolia Agricultural University,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学理学院,呼和浩特010018

出　　处：《现代应用物理》2024年第5期44-52,共9页Modern Applied Physics

基　　金：国家自然科学基金资助项目(12164033);内蒙古自治区自然科学基金资助项目(2023LHMS01003)。

摘　　要：在有效质量近似下,考虑压电场的影响,利用微扰法研究了闪锌矿和纤锌矿InAs/InP压电核/壳椭圆柱形量子点的一阶线性、三阶非线性以及总的光学吸收系数和折射率在不同核尺寸、杂质位置及椭圆率下的变化。结果表明:壳尺寸及杂质位置固定时,随着核尺寸的增大,吸收系数及折射率的峰值位置都出现红移现象,并且峰值强度增大;当杂质位置在径向ρ0变化时,随着ρ0的增大,吸收系数及折射率的峰值位置出现红移,伴随着峰值强度增加;随着椭圆率的增大,除杂质在量子点中心处,吸收系数和折射率的峰值位置发生明显蓝移,伴随着峰值强度出现不同程度的增加。当杂质位置在轴向z 0变化时,由于压电场和量子限域效应的综合影响,与z_(0)=-0.5 H时(H为量子点沿z轴的量子限域高度)相比,z_(0)=0,0.5 H时的吸收系数及折射率的峰值位置发生不同程度的蓝移。此外,与纤锌矿结构相比,闪锌矿结构中体系的吸收系数和折射率峰值位置整体发生较大的蓝移。Under the effective mass approximation,the first-order linear,third-order nonlinear,and total optical absorption coefficients(ACs)and refractive index changes(RICs)of the zinc-blende(ZB)and wurtzite(WZ)InAs/InP piezoelectric core/shell elliptic cylindrical quantum dots under different core sizes,impurity positions,and ellipticities are investigated by the perturbation method,taking into account the effect of piezoelectric field.The results show that as the core size increases,the peak positions of ACs and RICs both exhibit a redshift.When the impurity position changes in the radial directionρ0,asρ0 increases,the peak positions of ACs and RICs show a redshift,and accompanied by an increase in peak intensity.As the ellipticity increases,except the impurity in the center of the QD,the peak positions of ACs and RICs show an obvious blueshift with the variation of impurity position,and accompanied by the an increase of peak intensity in different degree.When the impurity position changes in the axial direction z 0,due to the combined influence of piezoelectric field and quantum confinement effect,compared with z_(0)=-0.5 H,the peak positions of ACs and RICs at z_(0)=0 and 0.5 H show a blueshift.In addition,compared with WZ structure,the peak positions of ACs and RICs in ZB structure show a significant blueshift.

关 键 词：椭圆柱形核/壳量子点 压电场 吸收系数 折射率 光学性质 

分 类 号：TL99[核科学技术—核技术及应用]