Important achievements in semiconductor quantum tr
Send: This station Date: 2019-10-18
The Key Laboratory of quantum information of the Chinese Academy of Sciences, led by academician Guo guangcan of the University of science and technology of China, has recently made important progress in the research of semiconductor gated quantum dots. Professor Guo Guoping's research group and his collaborators explored the possibility of applying two-dimensional layered transition metal chalcogenides to semiconductor quantum chips. For the first time, quantum dot devices with full electrical control have been realized in the flexible two-dimensional semiconductor material system.
After decades of development, semiconductor gated quantum dots as a kind of quantum transistors have become one of the hot candidate systems of quantum chips. Graphene as a representative of the two-dimensional material system because of its natural single atomic layer thickness, excellent electrical properties, easy integration and other advantages, has become the focus of flexible electronics, quantum electronics. However, in the ten years since the discovery of graphene, scientists have tried a lot of experiments and found that band structure, interface defects and impurities in graphene have a great impact on the performance of quantum dot devices. Until now, quantum dots in two-dimensional materials have not been able to achieve effective electrical regulation.
In view of this situation, Guo Guoping's research group, in cooperation with Takashi Taniguchi and Kenji Watanabe researchers of the National Institute of materials and Professor Franco nori of the Institute of physics and chemistry of Japan, selected a new two-dimensional material molybdenum disulfide for in-depth study. This material has suitable band gap, strong spin orbit coupling strength and abundant spin energy valley related physical phenomena, so it has a broad application prospect in quantum electronics, especially in spin electronics and energy Valley electronics.
After a large number of attempts, the research group used a series of modern semiconductor processing methods such as micro nano processing, low-temperature led irradiation, combined with the boron nitride packaging technology widely used in the current two-dimensional material system research, which effectively reduced the impurities and defects in the quantum dot structure. For the first time, a fully electronic controllable double quantum dot structure was realized in this kind of material.