论文标题
通过空间结构的光束刺激量子点的选择规则 - 应用于更高激发的激发激发函数的重建
Selection rules for the excitation of quantum dots by spatially structured light beams -- Application to the reconstruction of higher excited exciton wave functions
论文作者
论文摘要
应用于半导体量子点的空间结构化光场与均相梁的吸收光谱从根本上不同。在本文中，我们从理论上讨论了使用圆柱多极扩展的不同光束的所得光谱。对于量子点的描述，我们采用了一个基于有效质量近似（包括库仑和价带混合）的模型。单个空间结构的光束和状态混合的组合允许量子点中的所有激子状态在光学上可寻址。此外，我们证明可以对梁进行量身定制，以便无需光谱分离而有选择地激发单个状态。使用这种选择性，我们提出了一种测量量子点特征态的激子波函数的方法。通过揭示激子波函数的空间相信息，该测量超出了电子密度测量。从而通过包括无限较大的空间自由度来概括敏感的测量值。
Spatially structured light fields applied to semiconductor quantum dots yield fundamentally different absorption spectra than homogeneous beams. In this paper, we theoretically discuss the resulting spectra for different light beams using a cylindrical multipole expansion. For the description of the quantum dots we employ a model based on the effective mass approximation including Coulomb and valence band mixing. The combination of a single spatially structured light beam and state mixing allows all exciton states in the quantum dot to become optically addressable. Furthermore, we demonstrate that the beams can be tailored such that single states are selectively excited, without the need of spectral separation. Using this selectivity, we propose a method to measure the exciton wave function of the quantum dot eigenstate. The measurement goes beyond electron density measurements by revealing the spatial phase information of the exciton wave function. Thereby polarization sensitive measurements are generalized by including the infinitely large spatial degree of freedom.
