Using the effective mass and parabolic band approximations, and the finite element method, we calculate the combined effects of axially applied electric and magnetic fields on the electronic properties of cone-shaped quantum dots. Once the one particle eigenvalue equations have been solved, both for electrons and holes, the available information on energies and wave functions is used as input in order to calculate the electron and hole positions along the axial axis, the overlap integral, the ground state exciton lifetime, and the exciton Coulomb interaction; all these properties are obtained as a function of the applied electric and magnetic fields. The main findings are: (i) the electric field separates the electrons and holes in opposite positions of the structure, giving rise to indirect excitons with a quite significant lifetime, (ii) the magnetic field is a useful tool to increase by several orders of magnitude the exciton lifetime, mainly when it is superimposed on the electric field effect, (iii) for spatially direct excitons, the magnetic field reinforces the Coulomb integral giving rise to a redshift of the photoluminescence energy transition, (iv) the magnetic field effects are much more visible on electrons than on the holes, and finally (v) the electric field allows to tune the evolution of the structure from a quantum dot to a quantum ring. Our results on the photoluminescence energy transition are in excellent agreement with previously reported experimental measurements [Phys. Status Solidi RRL 2018 (2018) 1800245 (4pp)..].

使用有效的质量和抛物线能带近似，以及有限元方法，我们计算了轴向施加的电场和磁场对锥形量子点的电子特性的综合影响。一旦求解了一个粒子本征值方程，对于电子和空穴，就将有关能量和波函数的可用信息用作输入，以计算沿轴向的电子和空穴位置，重叠积分，基态激子寿命和激子库仑相互作用；获得的所有这些特性都取决于所施加的电场和磁场。主要发现有：（我）电场将电子和空穴在结构的相对位置分开，从而产生具有相当长寿命的间接激子;（ii）磁场是将激子寿命增加几个数量级的有用工具，主要是当它叠加在电场效应上，（iii）对于空间直接激子，磁场增强了库仑积分，引起光致发光能量跃迁的红移，（iv）磁场效应在电子上比在电子上更明显。孔，最后（v电场可以调节结构从量子点到量子环的演化。我们关于光致发光能量跃迁的结果与先前报道的实验测量结果非常吻合[Phys。状态Solidi RRL 2018 （2018） 1800245（4pp）..]。