Bejan Doina, Stan Cristina, Petrescu-Niță Alina
Faculty of Physics, University of Bucharest, 030018 Bucharest, Romania.
Faculty of Applied Sciences, National University of Science and Technology POLITEHNICA, 060042 Bucharest, Romania.
Nanomaterials (Basel). 2025 Jun 5;15(11):869. doi: 10.3390/nano15110869.
We investigate 3D quantum dot-double quantum ring structures of GaAs/AlGaAs submitted to the combined action of a non-resonant intense laser and an axial magnetic field. We study three representative geometries with the dot height larger, comparable or lower than the ring height. The intense laser field can change the confinement potential of the dot-double ring into dot-triple-ring or -multiple-ring potentials. Also, depending on the dot height, it increases/decreases the absorption of the structure. Under magnetic field, the energy spectra display Aharonov-Bohm oscillations characteristic of a single effective ring covering almost both rings, with a period controlled by the dot height. For large and medium dot height, the magnetic field lowers the absorption and leads to splitting and/or the apparition of two peaks, one that goes to red and the other to blue. In the presence of both fields, the spectra show different characteristics. The dot height and the external fields are thus proved to be efficient tools in controlling the absorption spectra, a useful feature in designing dot-double ring-based devices.
我们研究了处于非共振强激光和轴向磁场联合作用下的GaAs/AlGaAs三维量子点-双量子环结构。我们研究了三种具有代表性的几何结构，其中量子点高度大于、可比或小于环高度。强激光场可将点-双环的限制势变为点-三环或-多环势。此外，根据量子点高度的不同，它会增加/降低结构的吸收。在磁场作用下，能谱显示出阿哈罗诺夫-玻姆振荡，这是一个几乎覆盖两个环的单个有效环的特征，其周期由量子点高度控制。对于大、中量子点高度，磁场会降低吸收并导致分裂和/或出现两个峰，一个向红移，另一个向蓝移。在两种场都存在的情况下，光谱呈现出不同的特征。因此，量子点高度和外部场被证明是控制吸收光谱的有效工具，这在设计基于点-双环的器件中是一个有用的特性。
