By developing high-brightness single-photon source and high-temporal resolution single-photon imaging technology, researchers can directly observe the output results of two-dimensional walking mode of light quantum. Experiments show that quantum walking has different ballistic transmission characteristics from classical random walking in one-dimensional or two-dimensional evolution space. This accelerated transmission is the basis for quantum walking to surpass traditional computers in many algorithms. It has been pointed out that the transient network characteristics can only be realized in quantum walking with more than one dimension, and the previous quasi-two-dimensional quantum walking experiments can not observe the network propagation characteristics because of the limited quantum evolution space. In this study, the characteristics of transient network were successfully observed in the experiment for the first time, which further verified the two-dimensional characteristics of quantum walking.
It is one of the important research directions of quantum computer to develop fully electronically controlled semiconductor quantum chips compatible with modern semiconductor technology. Professor Guo's research group in Guo Guangcan's team has been committed to the research and development of semiconductor quantum chips for a long time. In recent years, semiconductor single-charge qubit universal logic gate and double-charge qubit controlled non-logic gate have been realized successively.
The so-called quantum chip is to integrate quantum circuits on the substrate and then carry the function of quantum information processing. Drawing lessons from the development of traditional computers, after overcoming the technical bottleneck, the research of quantum computers needs to take the road of integration in order to realize commercialization and industrial upgrading. At present, superconducting system, semiconductor quantum dot system, micro-nano photonics system and even atomic ion system all want to take the chip road. From the current development, superconducting quantum chip system is ahead of other physical systems in technology; The traditional semiconductor quantum dot system is also the goal that people are trying to explore at present, because after all, the development of the traditional semiconductor industry is very mature. For example, once the semiconductor quantum chip breaks through the threshold of fault-tolerant quantum computing in decoherence time and manipulation accuracy, it is expected to integrate the existing achievements of the traditional semiconductor industry and greatly save development costs.