Hartmann Nicolai F, Otten Matthew, Fedin Igor, Talapin Dmitri, Cygorek Moritz, Hawrylak Pawel, Korkusinski Marek, Gray Stephen, Hartschuh Achim, Ma Xuedan
Department of Chemistry and Center for NanoScience (CeNS), LMU Munich, 81377, Munich, Germany.
Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL, 60439, USA.
Nat Commun. 2019 Jul 22;10(1):3253. doi: 10.1038/s41467-019-11225-6.
Semiconductor quantum rings are topological structures that support fascinating phenomena such as the Aharonov-Bohm effect and persistent current, which are of high relevance in the research of quantum information devices. The annular shape of quantum rings distinguishes them from other low-dimensional materials, and enables topologically induced properties such as geometry-dependent spin manipulation and emission. While optical transition dipole moments (TDMs) in zero to two-dimensional optical emitters have been well investigated, those in quantum rings remain obscure despite their utmost relevance to the quantum photonic applications of quantum rings. Here, we study the dimensionality and orientation of TDMs in CdSe quantum rings. In contrast to those in other two-dimensional optical emitters, we find that TDMs in CdSe quantum rings show a peculiar in-plane linear distribution. Our theoretical modeling reveals that this uniaxial TDM originates from broken rotational symmetry in the quantum ring geometries.
半导体量子环是一种拓扑结构，支持诸如阿哈罗诺夫 - 玻姆效应和持续电流等引人入胜的现象，这些现象在量子信息设备研究中具有高度相关性。量子环的环形形状使其有别于其他低维材料，并能实现拓扑诱导特性，如与几何形状相关的自旋操控和发射。虽然零维到二维光学发射器中的光学跃迁偶极矩（TDMs）已得到充分研究，但量子环中的TDMs尽管与量子环的量子光子应用极为相关，却仍不清楚。在此，我们研究了CdSe量子环中TDMs的维度和取向。与其他二维光学发射器中的TDMs不同，我们发现CdSe量子环中的TDMs呈现出独特的面内线性分布。我们的理论模型表明，这种单轴TDM源自量子环几何结构中旋转对称性的破缺。
