An international first! Guo Guangcan's team made a breakthrough in room temperature control of solid spin color centers in two-dimensional materials
The team of Academician Guo Guangcan has made important progress in the field of solid-state spin color centers of two-dimensional materials.
In collaboration with Professor Adam Gali of Wegener Physics Research Center in Hungary, Li Quanfeng, Tang Jianshun, and Wang Yitao et al have reported a class of super-bright single-spin color centers with excellent optical and spin properties in hexagonal boron nitride (hBN). The coherent control at room temperature is realized.
Coherent control of an ultrabright single spin in hexagonal boron nitride at room temperature was presented in the article "Coherent control of an ultrabright single spin in hexagonal boron nitride at room temperature temperature), was published in the internationally renowned journal Nature Communications.
Solid-state spin color center is one of the important systems to realize quantum information technology. The most famous one is NV color center in diamond, which has made important progress in quantum computing, quantum sensing, quantum network and so on. In recent years, wide-band gap material hBN has been proved to be an excellent host of spin color centers. Because of its two-dimensional properties, it has special advantages over three-dimensional materials in the preparation of low-dimensional quantum devices and near-field sensing and detection. Spin color centers in hBN have become a research focus.
Spin color centers found in hBN include negatively charged boron vacancy (VB-) and several types of carbon-related color centers. Among them, VB- color center is the most widely studied spin color center in hBN. Li Chuanfeng and Tang Jianshun realized temperature sensing based on VB- color center [ACS Photonics 8, 1889 (2021)]. The coherent coupling and relaxation mechanism between electron spin and nuclear spin is revealed [Nature Communications 13, 5713 (2022)]. However, because of the low quantum efficiency of VB-, the single spin color center of VB- has not been discovered. Several single-spin color centers related to carbon have been reported recently, but coherent manipulation of single-spin color centers has not been demonstrated.
In this experiment, the research team effectively separated the single color center of hBN powder samples by capillary force, and found a class of super bright single spin color center with 85% probability by this method, which is 21 times higher than the previous single spin color center method. Subsequently, the research team characterized its excellent optical properties. The luminescence has significant photon anti-bunking characteristics, and the photon emissivity is as high as 25MHz, which is the highest fluorescence count in the single spin color center found in hBN. The team further performed room temperature coherent manipulation of the single spin color center, measured its Rabi oscillation signal, and carried out spin echo experiments.
Diagram of the hBN array
Optical properties of a single spin in hBN
Optically detected electron spin resonance of "Defect" A at room temperature
Room temperature coherent spin manipulation of "defect" A
The result of comparing this "defect" with the reported spin defect
This is the first time in the world to control the room temperature spin of the single spin color center in hBN, which is an important step to realize the application of quantum information by using the spin of two-dimensional materials. In order to clarify the structure of the color center, the team performed a first-principles theoretical calculation. The results showed that the complex of carbon and oxygen doping may be the source of the single spin color center. The simulated spectrum of CNCB3 model and the optical probe magnetic resonance signal were basically consistent with the experimental results.
Guo Naijie, postgraduates of the Key Laboratory of Quantum Information of Chinese Academy of Sciences, Liu Wei, postgraduates Yang Yuanze, Zeng Xiaodong, and Li Song, postdoctoral fellow of the Wgena Physics Research Center of Hungary, are co-first authors of the paper. The work was supported by the Ministry of Science and Technology, the National Natural Science Foundation of China, the Chinese Academy of Sciences and Anhui Province. Tang thanked the Youth Promotion Association of Chinese Academy of Sciences and Zhijiang Laboratory for the support of the Open project.
https://news.ustc.edu.cn/info/1055/83189.htm
