Formation of magnetic quantum wells based on oxide semiconductors and observation of magneto-optical effects

本研究的重点是发展基于量子阱结构的磁光材料。我们制备了磁性离子和激子空间分离的ZnCoO/ZnO量子威尔斯阱。ZnO和ZnCoO分别用作阱层和阻挡层。ZnCoO作为ZnO的量子势垒，并显示出大的s，p-d交换相互作用。此外，ZnCoO和ZnO之间的带偏移被确定为160毫电子伏，通过X射线光电子能谱测量。从X射线衍射，我们证实了高结晶度的ZnCoO/ZnO超晶格。最后，我们在量子威尔斯的能带边缘观察到自旋相关的塞曼分裂。然而，从量子威尔斯发射的激子抑制，因为在Co离子的电荷转移激发。

This study focuses on development of magneto-optical materials based on a quantum well structure. We fabricated ZnCoO/ZnO quantum wells with spatial separation between magnetic ions and excitons. ZnO and ZnCoO were used as well and barrier layers, respectively. ZnCoO acts as a quantum barrier for ZnO and shows large s,p-d exchange interaction. Furthermore, band offset between ZnCoO and ZnO was determined as 160 meV, as measured by x-ray photo-emission spectroscopy. From x-ray diffraction, we confirmed high crystallinity of ZnCoO/ZnO superlattices. Finally, we observed a spin-related Zeeman splitting at the band edge of the quantum wells. However, excitonic emissions from the quantum wells were suppressed because of charge-transfer excitation in a Co ion.